{"id":12240,"date":"2026-01-14T13:32:41","date_gmt":"2026-01-14T05:32:41","guid":{"rendered":"https:\/\/aobosteel.com\/?page_id=12240"},"modified":"2026-06-25T15:33:43","modified_gmt":"2026-06-25T07:33:43","slug":"s1-tool-steel-heat-treatment-guide","status":"publish","type":"page","link":"https:\/\/aobosteel.com\/es\/s1-tool-steel-heat-treatment-guide\/","title":{"rendered":"S1 Tool Steel Heat Treatment\u00a0Guide"},"content":{"rendered":"<section class=\"aobo-s1-heat-treatment-page\">\n  <style>\n    .aobo-s1-heat-treatment-page {\n      --aobo-blue: #0c56d0;\n      --aobo-blue-dark: #073b8e;\n      --aobo-blue-soft: #eaf2ff;\n      --aobo-border: #d7e5fb;\n      --aobo-text: #203044;\n      --aobo-muted: #617087;\n      --aobo-orange: #f59b23;\n      --aobo-white: #ffffff;\n      --aobo-shadow: 0 18px 45px rgba(12, 86, 208, 0.10);\n      --aobo-page-width: 1180px;\n      font-family: inherit;\n      color: var(--aobo-text);\n      line-height: 1.7;\n      background: transparent;\n  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<header class=\"aobo-hero\">\n      <h1>S1 Tool Steel Heat Treatment Guide<\/h1>\n      <p>S1 tool steel (1.2550, SKS41) is hardened by preheating to about 650\u00b0C (1200\u00b0F), austenitizing at 900\u00b0C to 955\u00b0C (1650\u00b0F to 1750\u00b0F), oil quenching to 50\u00b0C to 70\u00b0C, and tempering immediately while the part is still warm. As-quenched hardness runs about 57 to 59 HRC, and a double temper between 205\u00b0C and 315\u00b0C (400\u00b0F and 600\u00b0F) delivers the high toughness and shock resistance S1 is valued for. Rough-machined or cold-worked parts should be stress relieved before hardening.<\/p>\n    <\/header>\n\n    <section class=\"aobo-supply-block\" aria-label=\"S1 tool steel inquiry and product details\">\n      <div class=\"aobo-supply-image\">\n        <img decoding=\"async\" src=\"https:\/\/aobosteel.com\/wp-content\/uploads\/2025\/09\/S1-tool-steel.avif\" alt=\"S1 tool steel supplied by Aobo Steel\" loading=\"lazy\">\n      <\/div>\n      <div class=\"aobo-supply-content\">\n        <p>Aobo Steel supplies S1 tool steel (1.2550, SKS41) for shock-resisting applications. Send your required size, quantity, condition, and application for a quote.<\/p>\n        <div class=\"aobo-supply-actions\">\n          <a class=\"aobo-btn popmake-16052\" href=\"javascript:void(0);\">Enviar consulta<\/a>\n          <a class=\"aobo-btn aobo-btn-detail\" href=\"https:\/\/aobosteel.com\/es\/s1-tool-steel\/\">View S1 Tool Steel Details<\/a>\n        <\/div>\n      <\/div>\n    <\/section>\n\n    <main class=\"aobo-article\">\n      <h2>Stress Relief<\/h2>\n      <p>Stress relief prepares S1 components after rough machining or cold working, reducing the risk of distortion and cracking during hardening. Internal stresses from machining, if left in place, can cause severe microstructural or dimensional distortion once the part reaches hardening temperature.<\/p>\n      <ul class=\"aobo-list\">\n        <li><strong>Heating temperature:<\/strong> Heat uniformly to 650\u00b0C to 675\u00b0C (1200\u00b0F to 1250\u00b0F).<\/li>\n        <li><strong>Soak time:<\/strong> 1 hour per 25 mm (1 inch) of thickness, with a minimum of 1 hour.<\/li>\n        <li><strong>Cooling:<\/strong> Slow air cooling.<\/li>\n      <\/ul>\n\n      <h2>Precalentamiento<\/h2>\n      <p>To prevent thermal shock and excessive deformation, cold S1 workpieces must never be placed directly into a furnace already at austenitizing temperature.<\/p>\n      <ul class=\"aobo-list\">\n        <li><strong>Heating temperature:<\/strong> Slowly raise the temperature to about 650\u00b0C (1200\u00b0F).<\/li>\n        <li><strong>Soak:<\/strong> Hold until the cross-section is uniformly heated.<\/li>\n      <\/ul>\n      <p>For parts with complex geometry or large variations in cross-section, preheating is critical. It synchronizes the temperature rise between core and surface during final heating, which lowers thermal stress and prevents cracking.<\/p>\n\n      <h2>Austenitizing (Hardening)<\/h2>\n      <p>Austenitizing is the core hardening step. Heating transforms the structure to austenite and dissolves carbides into the matrix. The austenitizing temperature for S1 must be neither too high nor too low.<\/p>\n      <ul class=\"aobo-list\">\n        <li><strong>Heating temperature:<\/strong> 900\u00b0C to 955\u00b0C (1650\u00b0F to 1750\u00b0F).<\/li>\n        <li><strong>Hold time:<\/strong> 15 to 45 minutes, set by section thickness so the full cross-section through-hardens.<\/li>\n        <li><strong>Atmosphere:<\/strong> Because S1 has only moderate resistance to decarburization, heat in a controlled neutral atmosphere, vacuum, or neutral salt bath to prevent surface oxidation and carbon loss.<\/li>\n      <\/ul>\n\n      <h2>Temple<\/h2>\n      <p>S1 is an oil-hardening steel. Water quenching is occasionally used for large or simple sections, but oil quenching is preferred for the best toughness and the lowest risk of cracking.<\/p>\n      <ul class=\"aobo-list\">\n        <li><strong>Quenching medium:<\/strong> Preheated, circulating quenching oil.<\/li>\n        <li><strong>Procedure:<\/strong> Quench until the workpiece reaches 50\u00b0C to 70\u00b0C (120\u00b0F to 160\u00b0F), at which point it is still warm.<\/li>\n      <\/ul>\n      <p>Never let the part cool to room temperature before tempering. The as-quenched structure carries high internal stress, and delayed tempering leaves S1 highly prone to spontaneous brittle fracture.<\/p>\n\n      <figure class=\"aobo-figure\">\n        <img decoding=\"async\" src=\"https:\/\/aobosteel.com\/wp-content\/uploads\/2026\/01\/S1-tool-steel-Isothermal-Transformation-Diagram.avif\" alt=\"S1 tool steel isothermal transformation diagram\" loading=\"lazy\">\n        <figcaption>S1 isothermal transformation diagram for a grade with C 0.50%, Mn 0.25%, Si 0.75%, Cr 1.25%, V 0.20%, W 2.50%, austenitized at 925\u00b0C (1695\u00b0F). Source: Uddeholm.<\/figcaption>\n      <\/figure>\n\n      <h2>Templado<\/h2>\n      <p>Temper immediately after quenching to restore toughness and ductility. Tempering converts the as-quenched structure to tempered martensite, and the temperature is set by the hardness required.<\/p>\n      <ul class=\"aobo-list\">\n        <li><strong>Soak time:<\/strong> At least 2 hours per 25 mm (1 inch) of section thickness.<\/li>\n        <li><strong>Secondary tempering:<\/strong> A second temper is recommended to remove unstable retained austenite, improve yield strength and impact properties, and reduce the chance of later distortion or cracking in service.<\/li>\n        <li><strong>Cooling:<\/strong> Cool to room temperature between the first and second temper.<\/li>\n      <\/ul>\n      <p>Approximate hardness after oil quenching from 900\u00b0C to 955\u00b0C (1650\u00b0F to 1750\u00b0F):<\/p>\n      <div class=\"aobo-table-wrap\">\n        <table class=\"aobo-table\">\n          <thead>\n            <tr><th>Temperatura de templado<\/th><th>Approximate Hardness (HRC)<\/th><\/tr>\n          <\/thead>\n          <tbody>\n            <tr><td>A medida que se apaga<\/td><td>57 to 59<\/td><\/tr>\n            <tr><td>150\u00b0C (300\u00b0F)<\/td><td>56 to 58<\/td><\/tr>\n            <tr><td>205\u00b0C (400\u00b0F)<\/td><td>55 to 57<\/td><\/tr>\n            <tr><td>260\u00b0C (500\u00b0F)<\/td><td>54 to 56<\/td><\/tr>\n            <tr><td>315\u00b0C (600\u00b0F)<\/td><td>52 to 55<\/td><\/tr>\n            <tr><td>370\u00b0C (700\u00b0F)<\/td><td>50 to 53<\/td><\/tr>\n            <tr><td>425\u00b0C (800\u00b0F)<\/td><td>48 to 50<\/td><\/tr>\n            <tr><td>540\u00b0C (1000\u00b0F)<\/td><td>40 to 45<\/td><\/tr>\n          <\/tbody>\n        <\/table>\n      <\/div>\n      <p>For maximum toughness, as in chisels and heavy-duty punches, S1 is usually tempered between 205\u00b0C and 315\u00b0C (400\u00b0F and 600\u00b0F). Higher tempering temperatures can be used for warmer service conditions, but hardness drops significantly.<\/p>\n\n      <h2>Common Heat Treatment Problems and Solutions<\/h2>\n      <section class=\"aobo-problem\">\n        <h3>Quenching cracks<\/h3>\n        <p>Two causes dominate. The first is delayed tempering, where the part sits at room temperature after quenching long enough for stress to exceed the material&#8217;s strength. The second is stress concentration at sharp corners, stamp marks, or rough-machined surfaces. Temper immediately, transferring the part to the tempering furnace while it still holds residual heat near 50\u00b0C to 70\u00b0C. At the design and machining stage, use rounded corners at critical junctions and keep surfaces to a high finish.<\/p>\n      <\/section>\n      <section class=\"aobo-problem\">\n        <h3>Low hardness<\/h3>\n        <p>Common causes are surface decarburization from an improper austenitizing atmosphere, insufficient austenitizing temperature or hold time, and weak quenching from oil that is too hot or poorly agitated.<\/p>\n      <\/section>\n      <section class=\"aobo-problem\">\n        <h3>Deformation<\/h3>\n        <p>Deformation usually comes from thermal shock caused by heating too quickly, or from residual machining stress released during heating. Preheat to 650\u00b0C before hardening, stress relieve rough-machined parts before quenching, and support long or complex parts to prevent sagging.<\/p>\n      <\/section>\n      <section class=\"aobo-problem\">\n        <h3>Decarburized soft layer<\/h3>\n        <p>A soft surface layer forms when oxygen or moisture in the furnace reacts with surface carbon and carries it off as carbon monoxide or carbon dioxide. A quick check is to draw a file across the surface; if it scratches easily, a soft layer is present. To prevent it, use a vacuum furnace or an inert-gas atmosphere (nitrogen or argon) to exclude oxygen, calibrate salt baths regularly to keep them neutral, and leave enough grinding allowance so the decarburized layer can be removed after heat treatment.<\/p>\n      <\/section>\n\n      <section class=\"aobo-cta\">\n        <div>\n          <h2>Need S1 tool steel for shock-resisting applications?<\/h2>\n          <p>S1 tool steel (1.2550, SKS41) is used where high toughness and shock resistance are required. Send your required size, quantity, condition, and application for a quote.<\/p>\n        <\/div>\n        <a class=\"aobo-btn popmake-16052\" href=\"javascript:void(0);\">Enviar consulta<\/a>\n      <\/section>\n    <\/main>\n  <\/div>\n<\/section>\n\n\n\n<ul class=\"wp-block-yoast-seo-related-links yoast-seo-related-links\">\n<li><a href=\"https:\/\/aobosteel.com\/es\/s1-tool-steel\/\">S1 Tool Steel | 1.2550<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/aobosteel.com\/es\/h11-tool-steel-heat-treatment\/\">H11 Tool Steel Heat Treatment &amp; Hardness Chart<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/aobosteel.com\/es\/s7-tool-steel-rockwell-hardness-chart\/\">S7 Tool Steel Rockwell Hardness Chart | HRC, HB &amp; Working Range<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/aobosteel.com\/es\/o1-steel-hardness\/\">O1 Steel Hardness: Annealed, Quenched &amp; Tempered HRC Guide<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/aobosteel.com\/es\/h13-steel-heat-treatment\/\">H13 Heat Treatment Guide | Aobo Steel<\/a><\/li>\n<\/ul>\n\n\n\n<h2 id=\"h-faq\" class=\"wp-block-heading\">Preguntas frecuentes<\/h2>\n\n\n\n<div class=\"schema-faq wp-block-yoast-faq-block\"><div class=\"schema-faq-section\" id=\"faq-question-1768368514600\"><strong class=\"schema-faq-question\">What is the hardening temperature for S1 tool steel?<\/strong> <p class=\"schema-faq-answer\">The austenitizing heating temperature should be between 900\u00b0C and 955\u00b0C (1650\u00b0F and 1750\u00b0F). Hold this temperature for 15 to 45 minutes, depending on the workpiece thickness, to ensure complete through-hardening.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1768368531226\"><strong class=\"schema-faq-question\">How to perform stress relief on S1 tool steel?<\/strong> <p class=\"schema-faq-answer\">Heat the workpiece uniformly to 650\u00b0C\u2013675\u00b0C (1200\u00b0F\u20131250\u00b0F). Allow a soak time of 1 hour per 25 mm (1 inch) of thickness (minimum 1 hour), then cool slowly in air.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1768368533255\"><strong class=\"schema-faq-question\">What is the recommended quenching method for S1 steel?<\/strong> <p class=\"schema-faq-answer\">Oil quenching is strongly recommended to ensure optimal toughness and minimize cracking. Quench in preheated, circulating oil until the workpiece temperature drops to 50\u00b0C\u201370\u00b0C (120\u00b0F\u2013160\u00b0F).<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1768368534070\"><strong class=\"schema-faq-question\">How to prevent quenching cracks in S1 steel?<\/strong> <p class=\"schema-faq-answer\">Temper the workpiece immediately after quenching while it is still warm (50\u00b0C\u201370\u00b0C); do not let it cool to room temperature. Additionally, ensure designs use rounded corners rather than sharp stress points.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1768368534896\"><strong class=\"schema-faq-question\">What is the tempering process for S1 tool steel?<\/strong> <p class=\"schema-faq-answer\">Temper immediately after quenching with a minimum soak time of 2 hours per 25 mm (1 inch) of thickness. Secondary tempering is strongly recommended to achieve optimal yield strength and impact resistance.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1768368535752\"><strong class=\"schema-faq-question\">What hardness can S1 tool steel achieve?<\/strong> <p class=\"schema-faq-answer\">After oil quenching, S1 steel typically reaches an as-quenched hardness of 57\u201359 HRC. Tempering at temperatures between 205\u00b0C (400\u00b0F) and 315\u00b0C (600\u00b0F) results in a hardness range of 52\u201357 HRC.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1768368604242\"><strong class=\"schema-faq-question\">Why is preheating necessary for S1 steel?<\/strong> <p class=\"schema-faq-answer\">Preheating to 650\u00b0C (1200\u00b0F) prevents thermal shock and excessive deformation. It ensures synchronous core and surface heating during the final stage, reducing thermal stress and cracking risk for complex geometries.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1768368605375\"><strong class=\"schema-faq-question\">How to avoid soft layers or decarburization in S1 steel?<\/strong> <p class=\"schema-faq-answer\">Heat the steel in a vacuum furnace, neutral salt bath, or controlled neutral atmosphere to prevent surface oxidation. If decarburization occurs, leave sufficient tolerance to grind off the affected layer after heat treatment.<\/p> <\/div> <\/div>","protected":false},"excerpt":{"rendered":"<p>S1 Tool Steel Heat Treatment Guide S1 tool steel (1.2550, SKS41) is hardened by preheating to about 650\u00b0C (1200\u00b0F), austenitizing at 900\u00b0C to 955\u00b0C (1650\u00b0F to 1750\u00b0F), oil quenching to 50\u00b0C to 70\u00b0C, and tempering immediately while the part is still warm. As-quenched hardness runs about 57 to 59 HRC, and a double temper between [&hellip;]<\/p>\n","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":"set","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-12240","page","type-page","status-publish","hentry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v28.2 (Yoast SEO v28.2) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>S1 Tool Steel Heat Treatment\u00a0Guide - AoboSteel<\/title>\n<meta name=\"description\" content=\"Master the S1 tool steel heat treatment process. 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Hold this temperature for 15 to 45 minutes, depending on the workpiece thickness, to ensure complete through-hardening.","inLanguage":"es"},"inLanguage":"es"},{"@type":"Question","@id":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368531226","position":2,"url":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368531226","name":"How to perform stress relief on S1 tool steel?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Heat the workpiece uniformly to 650\u00b0C\u2013675\u00b0C (1200\u00b0F\u20131250\u00b0F). Allow a soak time of 1 hour per 25 mm (1 inch) of thickness (minimum 1 hour), then cool slowly in air.","inLanguage":"es"},"inLanguage":"es"},{"@type":"Question","@id":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368533255","position":3,"url":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368533255","name":"What is the recommended quenching method for S1 steel?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Oil quenching is strongly recommended to ensure optimal toughness and minimize cracking. Quench in preheated, circulating oil until the workpiece temperature drops to 50\u00b0C\u201370\u00b0C (120\u00b0F\u2013160\u00b0F).","inLanguage":"es"},"inLanguage":"es"},{"@type":"Question","@id":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368534070","position":4,"url":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368534070","name":"How to prevent quenching cracks in S1 steel?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Temper the workpiece immediately after quenching while it is still warm (50\u00b0C\u201370\u00b0C); do not let it cool to room temperature. Additionally, ensure designs use rounded corners rather than sharp stress points.","inLanguage":"es"},"inLanguage":"es"},{"@type":"Question","@id":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368534896","position":5,"url":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368534896","name":"What is the tempering process for S1 tool steel?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Temper immediately after quenching with a minimum soak time of 2 hours per 25 mm (1 inch) of thickness. Secondary tempering is strongly recommended to achieve optimal yield strength and impact resistance.","inLanguage":"es"},"inLanguage":"es"},{"@type":"Question","@id":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368535752","position":6,"url":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368535752","name":"What hardness can S1 tool steel achieve?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"After oil quenching, S1 steel typically reaches an as-quenched hardness of 57\u201359 HRC. Tempering at temperatures between 205\u00b0C (400\u00b0F) and 315\u00b0C (600\u00b0F) results in a hardness range of 52\u201357 HRC.","inLanguage":"es"},"inLanguage":"es"},{"@type":"Question","@id":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368604242","position":7,"url":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368604242","name":"Why is preheating necessary for S1 steel?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Preheating to 650\u00b0C (1200\u00b0F) prevents thermal shock and excessive deformation. It ensures synchronous core and surface heating during the final stage, reducing thermal stress and cracking risk for complex geometries.","inLanguage":"es"},"inLanguage":"es"},{"@type":"Question","@id":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368605375","position":8,"url":"https:\/\/aobosteel.com\/s1-tool-steel-heat-treatment-guide\/#faq-question-1768368605375","name":"How to avoid soft layers or decarburization in S1 steel?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Heat the steel in a vacuum furnace, neutral salt bath, or controlled neutral atmosphere to prevent surface oxidation. If decarburization occurs, leave sufficient tolerance to grind off the affected layer after heat treatment.","inLanguage":"es"},"inLanguage":"es"}]}},"uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false,"trp-custom-language-flag":false},"uagb_author_info":{"display_name":"Evan","author_link":"https:\/\/aobosteel.com\/es\/blog\/author\/admin\/"},"uagb_comment_info":0,"uagb_excerpt":"S1 Tool Steel Heat Treatment Guide S1 tool steel (1.2550, SKS41) is hardened by preheating to about 650\u00b0C (1200\u00b0F), austenitizing at 900\u00b0C to 955\u00b0C (1650\u00b0F to 1750\u00b0F), oil quenching to 50\u00b0C to 70\u00b0C, and tempering immediately while the part is still warm. As-quenched hardness runs about 57 to 59 HRC, and a double temper between&hellip;","rttpg_featured_image_url":null,"rttpg_author":{"display_name":"Evan","author_link":"https:\/\/aobosteel.com\/es\/blog\/author\/admin\/"},"rttpg_comment":0,"rttpg_category":null,"rttpg_excerpt":"S1 Tool Steel Heat Treatment Guide S1 tool steel (1.2550, SKS41) is hardened by preheating to about 650\u00b0C (1200\u00b0F), austenitizing at 900\u00b0C to 955\u00b0C (1650\u00b0F to 1750\u00b0F), oil quenching to 50\u00b0C to 70\u00b0C, and tempering immediately while the part is still warm. As-quenched hardness runs about 57 to 59 HRC, and a double temper between&hellip;","_links":{"self":[{"href":"https:\/\/aobosteel.com\/es\/wp-json\/wp\/v2\/pages\/12240","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/aobosteel.com\/es\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/aobosteel.com\/es\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/aobosteel.com\/es\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/aobosteel.com\/es\/wp-json\/wp\/v2\/comments?post=12240"}],"version-history":[{"count":0,"href":"https:\/\/aobosteel.com\/es\/wp-json\/wp\/v2\/pages\/12240\/revisions"}],"wp:attachment":[{"href":"https:\/\/aobosteel.com\/es\/wp-json\/wp\/v2\/media?parent=12240"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}