{"id":24965,"date":"2026-11-04T13:06:41","date_gmt":"2026-11-04T05:06:41","guid":{"rendered":"https:\/\/aobosteel.com\/?page_id=24965"},"modified":"2026-11-04T13:17:50","modified_gmt":"2026-11-04T05:17:50","slug":"4340-steel-properties","status":"publish","type":"page","link":"https:\/\/aobosteel.com\/ko\/4340-steel-properties\/","title":{"rendered":"4340 \uac15: \ud2b9\uc131, \uacbd\ub3c4 \ubc0f \uc5f4\ucc98\ub9ac"},"content":{"rendered":"<h1 id=\"h-4340-steel-properties\" class=\"wp-block-heading has-large-font-size\">4340 \uac15: \ud2b9\uc131, \uacbd\ub3c4 \ubc0f \uc5f4\ucc98\ub9ac<\/h1>\n\n\n\n<h2 id=\"h-what-is-4340-steel\" class=\"wp-block-heading\">4340 \uac15\uc774\ub780?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">4340\uc740 \uc911\ud0c4\uc18c \ub2c8\ucf08-\ud06c\ub86c-\ubab0\ub9ac\ube0c\ub374 \ud569\uae08\uac15(AISI\/SAE 4340)\uc785\ub2c8\ub2e4. \ucd08\uace0\uac15\ub3c4 \uad6c\uc870\uc6a9 \uac15\uc5d0 \uc18d\ud558\uba70 \uae4a\uc740 \uacbd\ud654\ub2a5, \uace0\uac15\ub3c4\uc5d0\uc11c\uc758 \ub192\uc740 \uc778\uc131, \uc6b0\uc218\ud55c \ud53c\ub85c \uc131\ub2a5\uc73c\ub85c \ud3c9\uac00\ubc1b\uc2b5\ub2c8\ub2e4. \ub300\ud45c\uc801\uc778 \ubd80\ud488\uc73c\ub85c\ub294 \ud56d\uacf5\uae30 \ucc29\ub959\uc7a5\uce58, \uc911\ud558\uc911 \uc0e4\ud504\ud2b8 \ubc0f \uc561\uc2ac, \uae30\uc5b4, \ud06c\ub7ad\ud06c\uc0e4\ud504\ud2b8 \ub4f1 \ub450\uaebc\uc6b4 \ub2e8\uba74\uc5d0\uc11c \ub192\uc740 \uc751\ub825\uc744 \ubc1b\ub294 \ubd80\ud488\uc774 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ub2c8\ucf08\uc740 4140\uacfc \uac19\uc740 \ud06c\ub86c-\ubab0\ub9ac\ube0c\ub374 \uac15\uacfc \uc774\ub97c \uad6c\ubd84\ud558\ub294 \uc694\uc18c\uc785\ub2c8\ub2e4. 1.65~2.00%\uc758 \ub2c8\ucf08\uc740 \uc778\uc131\uc744 \ub192\uc774\uace0, \ud06c\ub86c \ubc0f \ubab0\ub9ac\ube0c\ub374\uacfc \ud568\uaed8 \uc791\uc6a9\ud558\uc5ec \uacbd\ud654\ub2a5\uc744 \ub2e8\uba74 \uae4a\uc219\uc774\uae4c\uc9c0 \ud655\uc7a5\ud558\uba70, \uc800\uc628\uc5d0\uc11c\ub3c4 \uc720\uc6a9\ud55c \ucda9\uaca9 \ud2b9\uc131\uc744 \uc720\uc9c0\ud569\ub2c8\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\uc18c\uc7ac \uc120\uc815\uc5d0\uc11c \uc911\uc694\ud55c \uc810 \ud558\ub098: 4340\uc740 \ud569\uae08 \uad6c\uc870\uc6a9 \uac15\uc774\uc9c0 \uacf5\uad6c\uac15\uc774 \uc544\ub2d9\ub2c8\ub2e4. \uae08\ud615 \ubc0f \uc808\uc0ad \uc791\uc5c5\uc5d0 \ud544\uc694\ud55c \ub0b4\ub9c8\ubaa8\uc131\uc774\ub098 \uace0\uc628 \uacbd\ub3c4\ub97c \uc704\ud574 \uc124\uacc4\ub418\uc9c0 \uc54a\uc558\uc2b5\ub2c8\ub2e4. \uae08\ud615, \ud380\uce58 \ub610\ub294 \uc5f4\uac04 \uacf5\uad6c\uc6a9 \uc18c\uc7ac\ub97c \uc120\ud0dd\ud558\ub294 \uacbd\uc6b0\uc5d0\ub294 \uc544\ub798\uc758 \uacf5\uad6c\uac15\uacfc\uc758 \ube44\uad50\uac00 \uad00\ub828\uc774 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button\"><a class=\"wp-block-button__link wp-element-button\" href=\"https:\/\/aobosteel.com\/wp-content\/uploads\/2026\/11\/AISI-4340-Reference-Card.pdf\" download>4340 \uce74\ub4dc \ub2e4\uc6b4\ub85c\ub4dc, 412 KB<\/a><\/div>\n<\/div>\n\n\n\n<h2 id=\"h-4340-at-a-glance\" class=\"wp-block-heading\">4340 \uac1c\uc694<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>\uc131\uc9c8<\/td><td>\uc77c\ubc18\uc801\uc778 4340<\/td><td>\uc2e4\ubb34\uc5d0\uc11c\uc758 \uc758\ubbf8<\/td><\/tr><tr><td>Steel type<\/td><td>\ub2c8\ucf08-\ud06c\ub86c-\ubab0\ub9ac\ube0c\ub374 \ud569\uae08\uac15<\/td><td>\ub450\uaebc\uc6b4 \ub2e8\uba74\uc5d0\uc11c \ucd08\uace0\uac15\ub3c4<\/td><\/tr><tr><td>\uc5b4\ub2d0\ub9c1 \uacbd\ub3c4<\/td><td>217 HB<\/td><td>\uc77c\ubc18\uc801\uc73c\ub85c \uae30\uacc4\uac00\uacf5 \uc0c1\ud0dc\ub85c \uacf5\uae09\ub418\ub294 \ubc14<\/td><\/tr><tr><td>\ub2f4\uae08\uc9c8 \uc0c1\ud0dc \uacbd\ub3c4<\/td><td>13 mm\uc5d0\uc11c 58 HRC, 100 mm\uc5d0\uc11c 53 HRC<\/td><td>\ub2e8\uba74 \uae4a\uc219\uc774\uae4c\uc9c0 \uacbd\ub3c4 \uc720\uc9c0<\/td><\/tr><tr><td>\uc0ac\uc6a9 \uacbd\ub3c4<\/td><td>\ud15c\ud37c\ub9c1 \ud6c4 24~53 HRC<\/td><td>\ud15c\ud37c\ub9c1 \uc628\ub3c4\uac00 \uc218\uc900\uc744 \uacb0\uc815<\/td><\/tr><tr><td>\uc804\uccb4 \uacbd\ud654<\/td><td>75 mm\uae4c\uc9c0 \uc720\ub0c9, \ub354 \ud070 \ub2e8\uba74\uc740 \uc218\ub0c9<\/td><td>\uc218\ub0c9\uc740 \uade0\uc5f4 \uc704\ud5d8\uc744 \ub192\uc784<\/td><\/tr><tr><td>\ud53c\uc0ad\uc131<\/td><td>187~241 HB\uc5d0\uc11c AISI 1212\uc758 \uc57d 50%<\/td><td>\ub2c8\ucf08 \ub54c\ubb38\uc5d0 4140\ubcf4\ub2e4 \ub0ae\uc74c<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 id=\"h-chemical-composition\" class=\"wp-block-heading\">\ud654\ud559\uc801 \uc870\uc131<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>\uc694\uc18c<\/td><td>AISI 4340<\/td><td>JIS SNCM 439<\/td><td>GB 40CrNiMoA<\/td><\/tr><tr><td>Carbon (C)<\/td><td>0.38\u20130.43<\/td><td>0.36\u20130.43<\/td><td>0.37\u20130.44<\/td><\/tr><tr><td>\ub9dd\uac04 (Mn)<\/td><td>0.60\u20130.80<\/td><td>0.60\u20130.90<\/td><td>0.50\u20130.80<\/td><\/tr><tr><td>\uaddc\uc18c (Si)<\/td><td>0.15\u20130.35<\/td><td>0.15\u20130.35<\/td><td>0.17\u20130.37<\/td><\/tr><tr><td>\ub2c8\ucf08(Ni)<\/td><td>1.65\u20132.00<\/td><td>1.60\u20132.00<\/td><td>1.25\u20131.65<\/td><\/tr><tr><td>\ud06c\ub86c (Cr)<\/td><td>0.70\u20130.90<\/td><td>0.60\u20131.00<\/td><td>0.60\u20130.90<\/td><\/tr><tr><td>\ubab0\ub9ac\ube0c\ub374 (Mo)<\/td><td>0.20\u20130.30<\/td><td>0.15\u20130.30<\/td><td>0.15\u20130.25<\/td><\/tr><tr><td>\uc778(P)<\/td><td>\ucd5c\ub300 0.035<\/td><td>\ucd5c\ub300 0.030<\/td><td>\ucd5c\ub300 0.035<\/td><\/tr><tr><td>\ud669(S)<\/td><td>\ucd5c\ub300 0.040<\/td><td>\ucd5c\ub300 0.030<\/td><td>\ucd5c\ub300 0.035<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\uac12\uc740 %\uc785\ub2c8\ub2e4. \uc804\uae30\ub85c \uc7ac\uc9c8 E4340\uc740 \ub3d9\uc77c\ud55c \ubc94\uc704\ub97c \uc0ac\uc6a9\ud558\ub418 \uc794\ub958 \uc6d0\uc18c, \uc778 \ubc0f \ud669\uc774 \uac01\uac01 \ucd5c\ub300 0.025, \ub9dd\uac04\uc774 0.65~0.85\ub85c \ub354 \uc5c4\uaca9\ud569\ub2c8\ub2e4. \uac1c\uc7ac\ubb3c\uacfc \ud53c\ub85c \uc218\uba85\uc774 \uc911\uc694\ud55c \ud56d\uacf5\uc6b0\uc8fc \ub2e8\uc870\ud488 \ub4f1\uc5d0\uc11c \uc9c0\uc815\ub418\ub294 \ubc84\uc804\uc785\ub2c8\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ub2c8\ucf08 \ubc94\uc704\ub294 \uace0\uac1d\uc774 4340\uc744 \uc694\uccad\ud558\uace0 \uc81c\ucca0\uc18c\uac00 40CrNiMoA\ub97c \uc81c\uc548\ud560 \ub54c \ud655\uc778\ud574\uc57c \ud560 \uc218\uce58\uc785\ub2c8\ub2e4. \ub2c8\ucf08 1.25~1.65%\uc5d0\uc11c \uc911\uad6d \uc7ac\uc9c8\uc740 4340 \ubc94\uc704\uc758 \ud558\ud55c\uc5d0 \uc704\uce58\ud558\ubbc0\ub85c, \ubaa8\ub4e0 \uc6d0\uc18c\uac00 \uac01\uc790\uc758 \ubc94\uc704 \ub0b4\uc5d0 \uc788\ub354\ub77c\ub3c4 \ub450\uaebc\uc6b4 \ub2e8\uba74\uc740 \ub3c4\uba74\uc774 \uac00\uc815\ud55c \uacbd\ub3c4\uc5d0 \ubbf8\uce58\uc9c0 \ubabb\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n\n\n\n<h2 id=\"h-tempering-response\" class=\"wp-block-heading\">\ud15c\ud37c\ub9c1 \ubc18\uc751 \ubc0f \uae30\uacc4\uc801 \ud2b9\uc131<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">4340\uc740 \uc0ac\uc6a9 \uac00\ub2a5\ud55c \uc778\uc131\uc744 \uc720\uc9c0\ud558\uba74\uc11c \ub9e4\uc6b0 \ub192\uc740 \uac15\ub3c4\uc5d0 \ub3c4\ub2ec\ud558\uba70, \uc774 \uade0\ud615\uc774 \uc815\uc758\uc801\uc778 \ud2b9\uc131\uc785\ub2c8\ub2e4. \uc544\ub798 \ud45c\ub294 \uc720\ub0c9\ud55c 4340\uc758 \ud45c\uc900 \ud15c\ud37c\ub9c1 \ubc18\uc751\uc73c\ub85c, \uc628\ub3c4\uc5d0\uc11c \ucd5c\uc18c 2\uc2dc\uac04 \uc720\uc9c0\ud55c \uac83\uc785\ub2c8\ub2e4.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>\ub728\uc784<\/td><td>\uac15\ub3c4, MPa (\uc778\uc7a5 \/ \ud56d\ubcf5)<\/td><td>\uacbd\ub3c4 HB (HRC)<\/td><td>\uc544\uc774\uc870\ub4dc \ucda9\uaca9, J<\/td><\/tr><tr><td>205 \u00b0C<\/td><td>1980 \/ 1860<\/td><td>520 (53)<\/td><td>20<\/td><\/tr><tr><td>315 \u00b0C<\/td><td>1760 \/ 1620<\/td><td>490 (50)<\/td><td>14<\/td><\/tr><tr><td>425 \u00b0C<\/td><td>1500 \/ 1365<\/td><td>440 (46)<\/td><td>16<\/td><\/tr><tr><td>540 \u00b0C<\/td><td>1240 \/ 1160<\/td><td>360 (39)<\/td><td>47<\/td><\/tr><tr><td>650 \u00b0C<\/td><td>1020 \/ 860<\/td><td>290 (31)<\/td><td>100<\/td><\/tr><tr><td>705 \u00b0C<\/td><td>860 \/ 740<\/td><td>250 (24)<\/td><td>102<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\uacbd\ub3c4\ub9cc\uc774 \uc544\ub2c8\ub77c \ucda9\uaca9 \uc5f4\uc744 \uc77d\uc73c\uc2ed\uc2dc\uc624. 205 \u00b0C\uc5d0\uc11c 540 \u00b0C \uc0ac\uc774\uc5d0\uc11c \uacbd\ub3c4\ub294 \uc57d 160 HB \uac10\uc18c\ud558\ub294 \ubc18\uba74 \ud761\uc218 \uc5d0\ub108\uc9c0\ub294 \ub450 \ubc30 \uc774\uc0c1 \uc99d\uac00\ud569\ub2c8\ub2e4. \uc774 \ub54c\ubb38\uc5d0 4340\uc740 \uace0\uac15\ub3c4\uc5d0\uc11c \ucda9\uaca9\uc744 \uacac\ub38c\uc57c \ud558\ub294 \ubd80\ud488\uc5d0 \uc9c0\uc815\ub429\ub2c8\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">4340\uc744 \ud15c\ud37c\ub9c1\ud560 \ub54c \ub450 \uac00\uc9c0 \ucde8\ud654 \ud6a8\uacfc\uac00 \uc911\uc694\ud569\ub2c8\ub2e4:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\uac15\ud654\ub41c \ub9c8\ub974\ud150\uc0ac\uc774\ud2b8 \ucde8\uc131<\/strong> \u2014 230~370 \u00b0C \ubc94\uc704\uc758 \ud2b9\uc131 \uace8\uc9dc\uae30\ub85c, \uacbd\ub3c4\ub294 \uc5ec\uc804\ud788 \uc591\ud638\ud574 \ubcf4\uc774\uc9c0\ub9cc \ucda9\uaca9 \uc778\uc131\uc774 \ub5a8\uc5b4\uc9d1\ub2c8\ub2e4.<\/li>\n\n<li><strong>\uac00\uc5ed\uc801 \ud15c\ud37c \ucde8\uc131<\/strong> \u2014 \uace0\uc628 \ud15c\ud37c\ub9c1 \ud6c4 \uc57d 375~575 \u00b0C\ub97c \ud1b5\ud55c \uc11c\ub0c9\uc740 \uc778\uc774 \uad6c \uc624\uc2a4\ud14c\ub098\uc774\ud2b8 \uc785\uacc4\uc5d0 \ud3b8\uc11d\ub418\ub3c4\ub85d \ud569\ub2c8\ub2e4. \uae09\ub0c9\uacfc \uc774\uc911 \ud15c\ud37c\ub9c1\uc774 \uc774\ub97c \uc81c\ud55c\ud558\uba70, 4340\uc758 \ubab0\ub9ac\ube0c\ub374\uc740 \ubbfc\uac10\uc131\uc744 \uc904\uc774\uc9c0\ub9cc \uc81c\uac70\ud558\uc9c0\ub294 \uc54a\uc2b5\ub2c8\ub2e4.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\ub450 \ubc88\uc9f8 \ud6a8\uacfc \ub54c\ubb38\uc5d0 \ucda9\uaca9 \ub610\ub294 \ud53c\ub85c \ud558\uc911\uc744 \ubc1b\ub294 4340\uc5d0\ub294 455 \u00b0C \ubbf8\ub9cc\uc758 \ud15c\ud37c\ub9c1\uc774 \uad8c\uc7a5\ub418\uc9c0 \uc54a\uc2b5\ub2c8\ub2e4. \uc77c\ubd80 \ud56d\uacf5\uae30 \ubd80\ud488\ucc98\ub7fc \ucd5c\ub300 \uac15\ub3c4\uac00 \uc694\uad6c\ub418\ub294 \uacbd\uc6b0\uc5d0\ub294 \uc800\uc628 \uad6c\uac04\uc744 \uc774\uc911 \ud15c\ud37c\ub9c1 \ubc0f \uac80\uc99d\ub41c \uacf5\uc815\uacfc \ud568\uaed8 \uc0ac\uc6a9\ud569\ub2c8\ub2e4.<\/p>\n\n\n\n<h2 id=\"h-hardenability\" class=\"wp-block-heading\">\uacbd\ud654\ub2a5 \ubc0f \ub2e8\uba74 \ud06c\uae30<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\uae4a\uc740 \uacbd\ud654\ub2a5\uc740 \uc5d4\uc9c0\ub2c8\uc5b4\uac00 \ub354 \uc800\ud569\uae08 \uac15 \ub300\uc2e0 4340\uc744 \uc120\ud0dd\ud558\ub294 \uc774\uc720\uc785\ub2c8\ub2e4. \uc720\ub0c9\uc740 \uc9c1\uacbd 75 mm\uae4c\uc9c0\uc758 \uc6d0\ud615 \ub2e8\uba74\uc744 \uacbd\ud654\uc2dc\ud0a4\uba70, \ub354 \ud070 \ub2e8\uba74\uc740 \uc218\ub0c9\uc774 \ud544\uc694\ud558\uace0 \uc774\ub294 \uade0\uc5f4 \uc704\ud5d8\uc744 \ub192\uc785\ub2c8\ub2e4. 4140\uacfc \uac19\uc740 \uc800\ud569\uae08 \uc7ac\uc9c8\uc740 \uc791\uc740 \ubc14\uc5d0\uc11c\ub294 \uc798 \uacbd\ud654\ub418\uc9c0\ub9cc \ub450\uaebc\uc6b4 \ub2e8\uba74\uc758 \uc2ec\ubd80\uc5d0\uc11c\ub294 \uc5f0\ud654\ub429\ub2c8\ub2e4.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>\ubc14 \uc9c1\uacbd, \uc720\ub0c9<\/td><td>\ud45c\uba74 \uacbd\ub3c4 HRC<\/td><td>\uacbd\ub3c4 HB<\/td><\/tr><tr><td>13 mm (0.5 in)<\/td><td>58<\/td><td>614<\/td><\/tr><tr><td>25 mm (1 in)<\/td><td>57<\/td><td>596<\/td><\/tr><tr><td>50 mm (2 in)<\/td><td>56<\/td><td>577<\/td><\/tr><tr><td>100 mm (4 in)<\/td><td>53<\/td><td>528<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud574\ub2f9 \ubc94\uc704\uc5d0\uc11c\uc758 \uc190\uc2e4\uc740 \uc57d 5 HRC\uc785\ub2c8\ub2e4. 4140\uc5d0 \ub3d9\uc77c\ud55c \ube44\uad50\ub97c \uc801\uc6a9\ud558\uba74 \uac10\uc18c\ub294 8 HRC\uc5d0 \uac00\uae5d\uace0 75 mm\ub97c \ub118\uc73c\uba74 \uc2ec\ubd80\uac00 \ud6e8\uc52c \ube60\ub974\uac8c \ub5a8\uc5b4\uc9c0\uba70, \uc774\uac83\uc774 \ub450 \uc7ac\uc9c8\uc758 \uc2e4\uc9c8\uc801\uc778 \ucc28\uc774\uc785\ub2c8\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud15c\ud37c\ub9c1 \ud6c4\uc5d0\ub3c4 \uc774\uc810\uc740 \uc720\uc9c0\ub429\ub2c8\ub2e4. \uc720\ub0c9 \ud6c4 425 \u00b0C\uc5d0\uc11c \ud15c\ud37c\ub9c1\ud55c 4340\uc758 13, 38, 75 mm \ubc14\ub294 1460, 1450, 1420 MPa\ub97c \uc720\uc9c0\ud569\ub2c8\ub2e4. \uc218\ub0c9 \ud6c4 650 \u00b0C\uc5d0\uc11c \ud15c\ud37c\ub9c1\ud55c 75, 100, 150 mm \ubc14\ub294 340, 330, 322 HB\uc5d0\uc11c 1055, 1035, 1000 MPa\ub97c \uc720\uc9c0\ud569\ub2c8\ub2e4.<\/p>\n\n\n\n<h2 id=\"h-equivalent-grades\" class=\"wp-block-heading\">\uc0c1\uc751 \uac15\uc885<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>\ud45c\uc900<\/td><td>\ub4f1\uae09<\/td><td>\ud654\ud559 \uc131\ubd84, C \/ Mn \/ Si \/ Cr \/ Ni \/ Mo<\/td><\/tr><tr><td>ASTM A29\/A29M-03<\/td><td>4340 (G43400)<\/td><td>0.38\u20130.43 \/ 0.60\u20130.80 \/ 0.15\u20130.35 \/ 0.70\u20130.90 \/ 1.65\u20132.00 \/ 0.20\u20130.30<\/td><\/tr><tr><td>ASTM A29\/A29M-03<\/td><td>E4340 (G43406)<\/td><td>0.38\u20130.43 \/ 0.65\u20130.85 \/ 0.15\u20130.35 \/ 0.70\u20130.90 \/ 1.65\u20132.00 \/ 0.20\u20130.30<\/td><\/tr><tr><td>SAE J404 JUN00<\/td><td>4340 (G43400)<\/td><td>0.38\u20130.43 \/ 0.60\u20130.80 \/ 0.15\u20130.35 \/ 0.70\u20130.90 \/ 1.65\u20132.00 \/ 0.20\u20130.30<\/td><\/tr><tr><td>JIS G4053:2003<\/td><td>SNCM 439<\/td><td>0.36\u20130.43 \/ 0.60\u20130.90 \/ 0.15\u20130.35 \/ 0.60\u20131.00 \/ 1.60\u20132.00 \/ 0.15\u20130.30<\/td><\/tr><tr><td>GB(\uc911\uad6d)<\/td><td>40CrNiMoA<\/td><td>0.37\u20130.44 \/ 0.50\u20130.80 \/ 0.17\u20130.37 \/ 0.60\u20130.90 \/ 1.25\u20131.65 \/ 0.15\u20130.25<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">DIN 1.6565 (40NiCrMo6)\uc640 BS 817M40 (EN24)\uc740 \ub3d9\uc77c \uacc4\uc5f4\uc5d0 \uc18d\ud558\uba70, \uc720\ub7fd\uc5d0\uc11c 4340\uacfc \ud568\uaed8 \uac00\uc7a5 \uc790\uc8fc \uc778\uc6a9\ub418\ub294 \uba85\uce6d\uc785\ub2c8\ub2e4. \uc774\ub4e4\uc740 \uc0c1\ud638 \uad50\ud658 \uac00\ub2a5\ud55c \ubd80\ud488\uc774 \uc544\ub2c8\ub77c \uac00\uc7a5 \uadfc\uc811\ud55c \ub4f1\uae09\uc785\ub2c8\ub2e4. \ub2c8\ucf08 \ubc94\uc704, \ud669 \ud55c\ub3c4 \ubc0f \uacbd\ud654\ub2a5 \ubc94\uc704\uac00 \ubaa8\ub450 \uaddc\uaca9\ub9c8\ub2e4 \ub2ec\ub77c\uc9c0\uba70, \ud654\ud559 \uc131\ubd84\uc744 \ucda9\uc871\ud558\ub294 \ub4f1\uae09\uc774\ub77c\ub3c4 \ub3c4\uba74\uc5d0\uc11c \uac00\uc815\ud55c \ub2e8\uba74 \ud06c\uae30\uc5d0\uc11c \uacbd\ub3c4\ub97c \ucda9\uc871\ud558\uc9c0 \ubabb\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n\n\n\n<h2 id=\"h-heat-treatment\" class=\"wp-block-heading\">\uc5f4\ucc98\ub9ac<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>\ub2e8\uacc4<\/td><td>\uc628\ub3c4 \ubc0f \ube44\uace0<\/td><\/tr><tr><td>\uc815\uaddc\ud654<\/td><td>870\u2013925 \u00b0C, \ucd5c\uc18c 1\uc2dc\uac04 \ub610\ub294 25 mm\ub2f9 15\u201320\ubd84 \uc720\uc9c0, \uacf5\ub7ad<\/td><\/tr><tr><td>\uc5b4\ub2d0\ub9c1<\/td><td>830\u2013860 \u00b0C, \uc720\uc9c0, \uc57d 15 \u00b0C\/h\ub85c 480 \u00b0C\uae4c\uc9c0 \ub178\ub7ad, \uacf5\ub7ad<\/td><\/tr><tr><td>\uacbd\ud654<\/td><td>800\u2013845 \u00b0C, 25 mm\ub2f9 15\ubd84 \uc720\uc9c0, 25\u201360 \u00b0C\uc758 \ub530\ub73b\ud55c \uc624\uc77c\uc5d0\uc11c \ub2f4\uae08\uc9c8<\/td><\/tr><tr><td>\ub728\uc784<\/td><td>455\u2013650 \u00b0C\uc5d0\uc11c \ucd5c\uc18c 2\uc2dc\uac04 \uc720\uc9c0, \uacf5\ub7ad; 2\ud68c \ud15c\ud37c\ub9c1 \uad8c\uc7a5<\/td><\/tr><tr><td>\uc2a4\ud2b8\ub808\uc2a4 \ud574\uc18c<\/td><td>\uac00\uacf5 \ud6c4 \ubc0f \uacbd\ud654 \uc804 650\u2013675 \u00b0C, \uc774\ud6c4\uc5d0\ub294 \ud15c\ud37c\ub9c1 \uc628\ub3c4\ub97c \ucd08\uacfc\ud558\uc9c0 \ub9d0 \uac83<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">4140\uacfc \ub2e4\ub974\uba70 \ub193\uce58\uba74 \ube44\uc6a9\uc774 \ubc1c\uc0dd\ud558\ub294 \ub450 \uac00\uc9c0 \uc2e4\ubb34 \uc0ac\ud56d. \uccab\uc9f8, \uc624\uc2a4\ud14c\ub098\uc774\ud2b8\ud654 \ubc94\uc704\uac00 830\u2013870 \u00b0C \ub300\ube44 800\u2013845 \u00b0C\ub85c \ub354 \ub0ae\uc73c\uba70 \uc624\uc77c\uc740 \ub0c9\uc720\uac00 \uc544\ub2cc \uc628\uc720\ub97c \uc0ac\uc6a9\ud574\uc57c \ud569\ub2c8\ub2e4. \ub458\uc9f8, 4340\uc740 \uc77c\ubc18\uc801\uc73c\ub85c 2\ud68c \ud15c\ud37c\ub9c1\ud569\ub2c8\ub2e4. \uccab \ubc88\uc9f8 \ud15c\ud37c\ub9c1\uc740 \uc794\ub958 \uc624\uc2a4\ud14c\ub098\uc774\ud2b8\ub97c \ubcc0\ud0dc\uc2dc\ud0a4\uace0, \ub450 \ubc88\uc9f8\ub294 \uc778\uc131\uc744 \ud68c\ubcf5\uc2dc\ud0b5\ub2c8\ub2e4.<\/p>\n\n\n\n<h2 id=\"h-welding-4340\" class=\"wp-block-heading\">4340\uc758 \uc6a9\uc811<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">4340\uc740 \uc0ac\uc804 \uc778\uc99d\ub41c \uc6a9\uc811\uc6a9 \uac15\uc7ac\uac00 \uc544\ub2d9\ub2c8\ub2e4. \uc6a9\uc811 \uc808\ucc28\ub294 \ud574\ub2f9 \uc870\uc778\ud2b8\uc5d0 \ub9de\uac8c \uc791\uc131\ud558\uace0 \uc778\uc99d\ud574\uc57c \ud569\ub2c8\ub2e4.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\ub9c8\ub974\ud150\uc0ac\uc774\ud2b8 \uc2dc\uc791 \uc628\ub3c4 \uc774\uc0c1\uc73c\ub85c \uc608\uc5f4\ud558\uc5ec, <strong>290 \u00b0C (550 \u00b0F)<\/strong>, \uc5f4\uc601\ud5a5\ubd80\uac00 \ubbf8\ud15c\ud37c\ub9c1 \ub9c8\ub974\ud150\uc0ac\uc774\ud2b8 \ub300\uc2e0 \ubca0\uc774\ub098\uc774\ud2b8\ub85c \ubcc0\ud0dc\ud558\ub3c4\ub85d \ud569\ub2c8\ub2e4.<\/li>\n\n<li>\uc608\uc5f4\uc744 \uce35\uac04 \uc628\ub3c4\ub85c \uc720\uc9c0\ud558\uace0, \uc774\ubcf4\ub2e4 \ub0ae\uc544\uc9c0\uba74 \ubd80\ud488\uc744 \uc7ac\uac00\uc5f4\ud558\uc2ed\uc2dc\uc624.<\/li>\n\n<li>\uc800\uc218\uc18c \uacf5\uc815\uacfc \uc800\uc218\uc18c \uc18c\ubaa8\uc7ac\uac00 \ud544\uc218\uc785\ub2c8\ub2e4.<\/li>\n\n<li>\ud6c4\uc5f4\uc740 \ubd80\ud488\uc5d0 \uc801\uc6a9\ud55c \ud15c\ud37c\ub9c1 \uc628\ub3c4\ubcf4\ub2e4 28 \u00b0C (50 \u00b0F) \uc774\uc0c1 \ub192\uc9c0 \uc54a\uac8c \ud558\uc2ed\uc2dc\uc624.<\/li>\n<\/ul>\n\n\n\n<h2 id=\"h-machining-4340\" class=\"wp-block-heading\">4340\uc758 \uc808\uc0ad \uac00\uacf5<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">187~241 HB\uc758 \uc5b4\ub2d0\ub9c1 \uc0c1\ud0dc\uc5d0\uc11c 4340\uc740 AISI 1212\ub97c 100%\ub85c \ubcfc \ub54c \uc57d <strong>50%<\/strong> \uc758 \uc18d\ub3c4\ub85c \uac00\uacf5\ub429\ub2c8\ub2e4. \uc774\ub294 65%\uc778 4140\ubcf4\ub2e4 \ub290\ub9ac\uba70, \uadf8 \uc6d0\uc778\uc740 \ub2c8\ucf08\uc785\ub2c8\ub2e4. 255~363 HB\uc758 \ub2f4\uae08\uc9c8 \ubc0f \ud15c\ud37c\ub9c1 \uc0c1\ud0dc\uc5d0\uc11c\ub294 \ud3c9\uac00\uac00 \ub354 \ub0ae\uc544\uc9d1\ub2c8\ub2e4. \ub0ae\uc740 \uc18d\ub3c4, \ub354 \ub9ce\uc740 \uacf5\uad6c \ub9c8\ubaa8 \ubc0f \ub354 \uac15\uc131\uc774 \ub192\uc740 \uc14b\uc5c5\uc744 \uc608\uc0c1\ud574\uc57c \ud558\uc9c0\ub9cc, \uc774\ud6c4 \uc5f4\ucc98\ub9ac\ub85c \uc778\ud55c \ubcc0\ud615\uc740 \uc5c6\uc2b5\ub2c8\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">4340\uc73c\ub85c \uc77c\ubc18\uc801\uc73c\ub85c \uac00\uacf5\ub418\ub294 \ubd80\ud488\uc5d0\ub294 \ud53c\uc2a4\ud1a4 \ud540, \ubca0\uc5b4\ub9c1, \uae30\uc5b4, \uacf5\uc791\uae30\uacc4 \uc544\ubc84, \ub2e4\uc774 \ube14\ub85d \ubc0f \uc808\uc0ad \uacf5\uad6c \uc115\ud06c\uac00 \uc788\uc73c\uba70, \uc544\ub798\uc5d0 \ub098\uc5f4\ub41c \uad6c\uc870\uc6a9 \uc6a9\ub3c4\ub3c4 \ud3ec\ud568\ub429\ub2c8\ub2e4.<\/p>\n\n\n\n<h2 id=\"h-toughness\" class=\"wp-block-heading\">\uc778\uc131 \ubc0f \ud30c\uad34 \uc778\uc131<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\uc778\uc131\uc740 4340\uc774 \uc2e4\uc81c\ub85c \uad6c\ub9e4\ub418\ub294 \uc774\uc720\uc778 \ud2b9\uc131\uc774\uba70, \uacbd\ub3c4\uc640 \uc9c1\uc811\uc801\uc73c\ub85c \uc0c1\ucda9\ud569\ub2c8\ub2e4. \uc544\ub798 \ud45c\ub294 \ub3d9\uc77c\ud55c \uac15\uc7ac\ub97c \uc138 \uac00\uc9c0 \uc791\uc5c5 \uacbd\ub3c4\ub85c \ub098\ud0c0\ub0b8 \uac83\uc73c\ub85c, \ud3c9\uba74 \ubcc0\ud615 \ud30c\uad34 \uc778\uc131\uc744 \ucda9\uaca9 \uc5d0\ub108\uc9c0\uc640 \ud568\uaed8 \uce21\uc815\ud55c \uac12\uc785\ub2c8\ub2e4.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>\uacbd\ub3c4, HB<\/td><td>\uac15\ub3c4, MPa<\/td><td>\uc0e4\ub974\ud53c V-\ub178\uce58, J<\/td><td>K1c, MPa&middot;m&frac12;<\/td><\/tr><tr><td>550<\/td><td>2040<\/td><td>19<\/td><td>53<\/td><\/tr><tr><td>430<\/td><td>1520<\/td><td>30<\/td><td>75<\/td><\/tr><tr><td>380<\/td><td>1290<\/td><td>42<\/td><td>110<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud589\uc744 \uc67c\ucabd\uc5d0\uc11c \uc624\ub978\ucabd\uc73c\ub85c \uc77d\uc5b4 \ubcf4\uc2ed\uc2dc\uc624. 380 HB\uc5d0\uc11c 550 HB\ub85c \uc62c\ub77c\uac00\uba74 \uac15\ub3c4\ub294 \uc57d 60\ud37c\uc13c\ud2b8 \ub192\uc544\uc9c0\uace0 \ud30c\uad34 \uc778\uc131\uc740 \uc808\ubc18\uc73c\ub85c \ub5a8\uc5b4\uc9d1\ub2c8\ub2e4. 110\uc5d0\uc11c 53 MPa\u00b7m\u00bd\uc785\ub2c8\ub2e4. \ud45c\uc758 \uac15\ub3c4 \uac12\uc740 \uacbd\ub3c4\uc5d0\uc11c \ucd94\uc815\ud55c \uac83\uc774\ubbc0\ub85c \uce21\uc815 \ub370\uc774\ud130\uac00 \uc544\ub2c8\ub77c \ub300\uc751 \uad00\uacc4\ub85c \ubcf4\uc2ed\uc2dc\uc624. \ub3c4\uba74\uc774 550 HB\uc758 4340\uc744 \uc694\uad6c\ud55c\ub2e4\uba74 \uc190\uc0c1\uc5d0 \ub300\ud55c \uc5ec\uc720\uac00 \uac70\uc758 \uc5c6\ub294 \ubd80\ud488\uc744 \uc694\uad6c\ud558\ub294 \uac83\uc774\uba70, \uc124\uacc4\uac00 \uc774\ub97c \uac10\uc548\ud574\uc57c \ud569\ub2c8\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\uc54c\uc544\ub458 \ub9cc\ud55c \uad00\ub828 \ub4f1\uae09: 300M\uc740 \uaddc\uc18c\ub85c \uac1c\ub7c9\ub41c 4340\uc73c\ub85c, \uaddc\uc18c \uc57d 1.6\ud37c\uc13c\ud2b8\uc5d0 \ud0c4\uc18c\uc640 \ubab0\ub9ac\ube0c\ub374\uc774 \uc57d\uac04 \ub354 \ub192\uace0 \uc18c\ub7c9\uc758 \ubc14\ub098\ub4d0\uc774 \ucca8\uac00\ub418\uc5b4 \uc788\uc2b5\ub2c8\ub2e4. \uaddc\uc18c\ub294 \ub3d9\uc77c\ud55c \uac15\ub3c4\uc5d0\uc11c \ub354 \ub192\uc740 \ud15c\ud37c\ub9c1 \uc628\ub3c4\ub97c \uac00\ub2a5\ud558\uac8c \ud558\uc5ec \uc778\uc131\uc744 \ud5a5\uc0c1\uc2dc\ud0b5\ub2c8\ub2e4. \ub610\ud55c \uc5f4\ucc98\ub9ac \uc911 \ud0c8\ud0c4 \uacbd\ud5a5\uc774 \ub354 \ud06c\ubbc0\ub85c \uc77c\ubc18 4340\ubcf4\ub2e4 \ud45c\uba74 \ubcf4\ud638\uac00 \ub354 \uc911\uc694\ud569\ub2c8\ub2e4.<\/p>\n\n\n\n<h2 id=\"h-4340-vs-4140\" class=\"wp-block-heading\">4340 \ub300 4140<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">4140\uacfc 4340\uc740 \ud06c\ub86c-\ubab0\ub9ac\ube0c\ub374 \uae30\ubc18\uc744 \uacf5\uc720\ud558\uba70, \ucc28\uc774\ub294 \ub2c8\ucf08\uc785\ub2c8\ub2e4. 4140\uc5d0\ub294 \uc0ac\uc2e4\uc0c1 \ub2c8\ucf08\uc774 \uc5c6\uace0, 4340\uc5d0\ub294 1.65~2.00%\uac00 \ud568\uc720\ub418\uc5b4 \uc788\uc73c\uba70, \uc774 \ub2e8\uc77c \ucca8\uac00\uac00 \ub3c4\uba74 \uac80\ud1a0\uc5d0\uc11c \ub450 \uac15\uc7ac\ub97c \uad6c\ubd84\ud558\ub294 \uc694\uc18c\uc785\ub2c8\ub2e4.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>\uc131\uc9c8<\/td><td>4340<\/td><td>4140<\/td><\/tr><tr><td>\uc2ec\uce35 \uacbd\ud654\uc131<\/td><td>\ud5d8\uc900\ud55c \uc9c0\ud615\uc5d0\uc11c \ud0c1\uc6d4\ud55c \uc131\ub2a5\uc744 \ubc1c\ud718\ud569\ub2c8\ub2e4.<\/td><td>\ubcf4\ud1b5\uc758<\/td><\/tr><tr><td>\uc804\uccb4 \uacbd\ud654<\/td><td>75 mm\uae4c\uc9c0 \uc720\ub2f4\uae08\uc9c8<\/td><td>75\u2013100 mm \uc774\uc0c1\uc5d0\uc11c \uc2ec\ubd80\uac00 \uc5f0\ud654\ub428<\/td><\/tr><tr><td>100 mm\uc5d0\uc11c\uc758 \uacbd\ub3c4<\/td><td>\ub2f4\uae08\uc9c8 \uc0c1\ud0dc 53 HRC<\/td><td>\uc804\uccb4 \uacbd\ud654\ub418\uc9c0 \uc54a\uc74c<\/td><\/tr><tr><td>\uace0\uac15\ub3c4\uc5d0\uc11c\uc758 \uc778\uc131<\/td><td>\ud6cc\ub96d\ud55c<\/td><td>\uc88b\uc740<\/td><\/tr><tr><td>\uc800\uc628 \uc778\uc131<\/td><td>\uc88b\uc740<\/td><td>\uc801\uc808\ud55c<\/td><\/tr><tr><td>\uc0c1\ub300\uc801 \ube44\uc6a9<\/td><td>\ub2c8\ucf08\ub85c \uc778\ud574 \ub354 \ub192\uc74c<\/td><td>\ub0ae\uc74c<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">4140\uc774 \uc804\uccb4 \uacbd\ud654\ud560 \uc218 \uc5c6\ub294 \ub2e8\uba74\uc5d0\uc11c \uc804\uccb4 \uacbd\ub3c4\uac00 \ud544\uc694\ud560 \ub54c, \uace0\uac15\ub3c4\uc5d0\uc11c \ucd5c\ub300 \uc778\uc131\uc774 \uc694\uad6c\ub420 \ub54c, \ud56d\uacf5\uae30 \ubd80\ud488 \ubc0f \uc911\ud558\uc911 \uc0e4\ud504\ud2b8\uc640 \uac19\uc774 \ud53c\ub85c \ud558\uc911\uc744 \ubc1b\ub294 \ubd80\ud488\uc77c \ub54c, \ub610\ub294 \uc800\uc628 \uc778\uc131\uc774 \uc911\uc694\ud560 \ub54c 4140 \ub300\uc2e0 4340\uc744 \uc120\ud0dd\ud558\uc2ed\uc2dc\uc624. \uc911\uac04 \uac15\ub3c4\uc758 \ub354 \uc587\uc740 \ub2e8\uba74\uc5d0\ub294 4140\uc774 \ub354 \uacbd\uc81c\uc801\uc778 \ub2f5\uc785\ub2c8\ub2e4.<\/p>\n\n\n\n<h2 id=\"h-4340-vs-tool-steel\" class=\"wp-block-heading\">4340 \ub300 \uacf5\uad6c\uac15<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\ub9ce\uc740 \uad6c\ub9e4\uc790\ub4e4\uc774 \uc774 \ud398\uc774\uc9c0\ub97c \ucc3e\ub294 \uc774\uc720\uac00 \ubc14\ub85c \uc774 \uc810 \ub54c\ubb38\uc774\ubbc0\ub85c, \uba85\ud655\ud558\uac8c \uc124\uba85\ud558\ub294 \uac83\uc774 \uc911\uc694\ud569\ub2c8\ub2e4. 4340\uac15\uc740 \uae08\ud615 \ubc0f \uc808\uc0ad \uac00\uacf5 \uc791\uc5c5\uc5d0\uc11c \uacf5\uad6c\uac15\uc744 \ub300\uccb4\ud560 \uc218 \uc5c6\uc2b5\ub2c8\ub2e4.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>\uc694\uad6c \uc0ac\ud56d<\/td><td>4340<\/td><td>\uacf5\uad6c\uac15 (D2 \/ H13)<\/td><\/tr><tr><td>\ub0b4\ub9c8\ubaa8\uc131<\/td><td>\ub0ae\uc740<\/td><td>\ud0c4\ud654\ubb3c \ubd80\ud53c\ub85c \uc778\ud574 \ub192\uc74c<\/td><\/tr><tr><td>\uace0\uc628 \uacbd\ub3c4<\/td><td>\uac00\ub09c\ud55c<\/td><td>\uc88b\uc74c(H13)<\/td><\/tr><tr><td>\uc5e3\uc9c0 \uc720\uc9c0<\/td><td>\uac00\ub09c\ud55c<\/td><td>\uc88b\uc740<\/td><\/tr><tr><td>\ucd5c\ub300 \uc2e4\uc81c \uacbd\ub3c4<\/td><td>~50\u201355 HRC<\/td><td>58\u201364 HRC<\/td><\/tr><tr><td>\uad6c\uc870\uc801 \uac15\ub3c4\uc640 \uc778\uc131<\/td><td>\ud6cc\ub96d\ud55c<\/td><td>\ubcf4\ud1b5\uc758<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">4340\uc740 \ubd80\ud488\uc774 \uad6c\uc870\uc6a9\uc774\uba70 \uc0c1\uc628 \ub610\ub294 \uc911\uac04 \uc628\ub3c4\uc5d0\uc11c \uadf9\ud55c\uc758 \uac15\ub3c4\uc640 \uc778\uc131\uc774 \ud544\uc694\ud560 \ub54c \uc6b0\uc218\ud569\ub2c8\ub2e4. \uacf5\uad6c\uac15\uc740 \ubd80\ud488\uc774 \ub0b4\ub9c8\ubaa8\uc131, \uc808\uc0ad\ub0a0 \uc720\uc9c0 \ub610\ub294 \uace0\uc628 \uacbd\ub3c4 \uc720\uc9c0\ub97c \ud544\uc694\ub85c \ud560 \ub54c \uc6b0\uc218\ud569\ub2c8\ub2e4. \ub0c9\uac04 \uac00\uacf5 \ub2e4\uc774\uc5d0\ub294 D2 \ub610\ub294 A2\uac00 \uc801\ud569\ud569\ub2c8\ub2e4. \uc5f4\uac04 \uac00\uacf5 \ub2e4\uc774 \ub610\ub294 \uc555\ucd9c \uacf5\uad6c\uc5d0\ub294 H13 \ub610\ub294 H11\uc774 \uc801\ud569\ud569\ub2c8\ub2e4. \uc774\ub7ec\ud55c \uc5ed\ud560\uc5d0 4340\uc744 \uc0ac\uc6a9\ud558\uba74 \ub354 \uc800\ub834\ud55c \ub2e4\uc774\uac00 \uc544\ub2c8\ub77c \uc870\uae30 \ub9c8\ubaa8\uc640 \ubcc0\ud615\uc744 \ucd08\ub798\ud569\ub2c8\ub2e4.<\/p>\n\n\n\n<h2 id=\"h-applications\" class=\"wp-block-heading\">\uc77c\ubc18\uc801\uc778 \uc751\uc6a9 \ubd84\uc57c<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">4340\uc740 \ud56d\uacf5\uae30 \ucc29\ub959 \uc7a5\uce58 \ubc0f \uad6c\uc870\uc6a9 \ud53c\ud305, \ud5ec\ub9ac\ucf65\ud130 \ubc0f \ud30c\uc6cc\ud2b8\ub808\uc778 \uc0e4\ud504\ud2b8, \uc911\ud558\uc911 \uc561\uc2ac \ubc0f \uad6c\ub3d9 \uc0e4\ud504\ud2b8, \uae30\uc5b4, \ud06c\ub7ad\ud06c\uc0e4\ud504\ud2b8, \uace0\uac15\ub3c4 \ubcfc\ud2b8 \ubc0f \ucd1d\uc5f4\uc5d0 \uc0ac\uc6a9\ub429\ub2c8\ub2e4. \ud53c\ub85c\uac00 \uc911\uc694\ud55c \ud56d\uacf5\uc6b0\uc8fc \ubd80\ud488\uc740 \uc885\uc885 \uac1c\uc7ac\ubb3c\uc744 \uc904\uc774\uace0 \ud53c\ub85c \uc218\uba85\uc744 \ub192\uc774\uae30 \uc704\ud574 \uc9c4\uacf5 \uc7ac\uc6a9\ud574\ub41c 4340, VAR \ub610\ub294 ESR\ub85c \uc81c\uc870\ub418\ub294\ub370, \uccad\uc815\ud55c \uac15\uc7ac\ub294 \ubc18\ubcf5 \ud558\uc911\uc5d0\uc11c \uade0\uc5f4 \uac1c\uc2dc\uc5d0 \ub354 \uc798 \uc800\ud56d\ud558\uae30 \ub54c\ubb38\uc785\ub2c8\ub2e4.<\/p>\n\n\n\n<h2 id=\"h-standards-and-references\" class=\"wp-block-heading\">\ud45c\uc900 \ubc0f \ucc38\uace0 \uc790\ub8cc<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">4340\uc740 \ubd09\uc7ac\uc758 \uacbd\uc6b0 ASTM A29\/A29M \ubc0f SAE J404, \ube4c\ub9bf \ubc0f \ubd09\uc7ac\uc758 \uacbd\uc6b0 ASTM A322, \ud56d\uacf5\uc6b0\uc8fc\uc6a9 \ubd09\uc7ac \ubc0f \ub2e8\uc870\ud488\uc758 \uacbd\uc6b0 AMS \uaddc\uaca9\uc758 \uc801\uc6a9\uc744 \ubc1b\uc2b5\ub2c8\ub2e4. \ub4f1\uac00 \ub4f1\uae09\uc740 JIS G4053 (SNCM439) \ubc0f GB\/T 3077 (40CrNiMoA)\uc5d0 \uc788\uc2b5\ub2c8\ub2e4. \uc778\uc99d\ub41c \uae30\uacc4\uc801 \uc131\uc9c8\uc740 \ud56d\uc0c1 \uba85\uc2dc\ub41c \uaddc\uaca9, \ub2e8\uba74 \ud06c\uae30 \ubc0f \uc2dc\ud5d8 \uc704\uce58\uc640 \uc5f0\uacb0\ub418\uc5b4\uc57c \ud569\ub2c8\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\uc774 \ud398\uc774\uc9c0\uc758 \ub370\uc774\ud130:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\ud15c\ud37c\ub9c1 \ubc18\uc751, \uc9c8\ub7c9 \ud6a8\uacfc \ubc0f \uc5f4\ucc98\ub9ac \uc2e4\ubb34 \u2014 ASM Handbook Vol. 4, Heat Treating, 4340 \ud56d\ubaa9.<\/li>\n\n<li>\uc5b4\ub2d0\ub9c1, \ub178\uba40\ub77c\uc774\uc9d5 \ubc0f \ud15c\ud37c\ub9c1 \uacbd\ub3c4 \ubc94\uc704, \ub2e8\uba74 \ud06c\uae30\ubcc4 \uacbd\ub3c4, \ud53c\uc0ad\uc131 \ud3c9\uac00 \ubc0f \ub300\ud45c \ubd80\ud488 \u2014 Cutting Data for Turning of Steel, AISI 4340 \uc7a5.<\/li>\n\n<li>\ub4f1\uac00 \ub4f1\uae09 \ubc0f \ud654\ud559 \uc131\ubd84 \u2014 Handbook of Comparative World Steel Standards (ASTM DS 67B), Ni-Cr-Mo \uac15 \ud45c.<\/li>\n\n<li>GB 40CrNiMoA \ud654\ud559 \uc131\ubd84 \u2014 \u901a\u7528\u94a2\u94c1\u6750\u6599 (\uc911\uad6d \uac15\uc7ac \ud578\ub4dc\ubd81).<\/li>\n\n<li>\uc6a9\uc811 \uc2e4\ubb34 \u2014 ASM Handbook Vol. 6, Welding, Brazing and Soldering.<\/li>\n\n<li>AISI 4340 \ucc38\uace0 \uce74\ub4dc, PDF 2\ud398\uc774\uc9c0, 412 KB. PDF\ub294 \uc601\uc5b4\ub85c \uc81c\uacf5\ub429\ub2c8\ub2e4. \ub3d9\uc77c\ud55c \ud45c\ub97c \uc778\uc1c4\uc6a9\uc73c\ub85c \uc81c\uacf5\ud569\ub2c8\ub2e4.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\uad00\ub828 \uc790\ub8cc:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/aobosteel.com\/ko\/4140-steel-properties\/\">4140 \uac15\uc7ac \ud2b9\uc131 \ubc0f \uc5f4\ucc98\ub9ac<\/a><\/li>\n\n<li><a href=\"https:\/\/aobosteel.com\/ko\/4140-vs-h13\/\">4140 \uacf5\uad6c\uac15 vs H13 \uacf5\uad6c\uac15<\/a><\/li>\n\n<li><a href=\"https:\/\/aobosteel.com\/ko\/d2-steel-vs-4140\/\">4140 vs D2 \uacf5\uad6c\uac15<\/a><\/li>\n\n<li><a href=\"https:\/\/aobosteel.com\/ko\/what-is-tool-steel\/\">\uacf5\uad6c\uac15\uc774\ub780 \ubb34\uc5c7\uc778\uac00<\/a><\/li>\n\n<li><a href=\"https:\/\/aobosteel.com\/ko\/how-to-select-tool-steels\/\">\uacf5\uad6c\uac15 \ub4f1\uae09 \uc120\ud0dd \uac00\uc774\ub4dc<\/a><\/li>\n\n<li><a href=\"https:\/\/aobosteel.com\/ko\/h13-tool-steel\/\">H13 \uacf5\uad6c\uac15<\/a><\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>4340 (40CrNiMoA \/ SNCM439) nickel-chromium-molybdenum steel: tempering response, hardness by section size, equivalent grades, welding and machinability.<\/p>","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"normal-width-container","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"disabled","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"class_list":["post-24965","page","type-page","status-publish","hentry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v28.8 (Yoast SEO v28.8) - 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