{"id":176,"date":"2026-02-27T02:09:40","date_gmt":"2026-02-27T02:09:40","guid":{"rendered":"https:\/\/sdballs.com\/product\/aisi-420a-420b-stainless-steel-balls\/"},"modified":"2026-06-25T01:15:43","modified_gmt":"2026-06-25T01:15:43","slug":"aisi-420a-420b-stainless-steel-balls","status":"publish","type":"product","link":"https:\/\/sdballs.com\/es\/product\/aisi-420a-420b-stainless-steel-balls\/","title":{"rendered":"AISI 420A\/420B Stainless Steel Balls &#8211; Hardened Martensitic Stainless Steel Balls"},"content":{"rendered":"<h2 id=\"product-overview\" class=\"wp-block-heading\">Descripci\u00f3n general del producto<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">AISI 420A\/420B Stainless Steel Balls belong to the martensitic stainless steel ball family. Their key advantage is that they can be hardened by heat treatment, giving them higher hardness and wear resistance than 300-series austenitic stainless steel balls. This makes them suitable for mechanical parts where both wear resistance and moderate corrosion resistance are required.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For buyers, the main value of AISI 420A\/420B is practical performance at a reasonable cost: the material provides useful stainless corrosion resistance in water, steam, oil and petrol environments while maintaining a hardened, wear-resistant surface. These balls are often selected for special bearings, pump components, safety belt mechanisms, lighters, ballpoint pens and other mechanical assemblies where AISI 420C or AISI 440C may be unnecessary or over-specified.<\/p>\n\n\n\n<h2 id=\"material-selection-technical-positioning\" class=\"wp-block-heading\">Material Selection &amp; Technical Positioning<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">AISI 420A and AISI 420B are hardenable martensitic stainless steels. They should be positioned between non-hardened 300-series stainless steel balls and higher-carbon hardened stainless steel balls such as AISI 420C and AISI 440C.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Compared with AISI 304\/316 stainless steel balls: AISI 420A\/420B offers higher hardness and wear resistance, but lower corrosion resistance in aggressive or chloride environments.<\/li>\n\n\n\n<li>Compared with AISI 420C stainless steel balls: AISI 420A\/420B is used when required hardness and wear resistance are lower.<\/li>\n\n\n\n<li>Compared with AISI 440C stainless steel balls: AISI 420A\/420B usually offers lower hardness and wear resistance, but may be more economical for non-critical stainless applications.<\/li>\n\n\n\n<li>Compared with AISI 52100 chrome steel balls: AISI 420A\/420B provides stainless corrosion resistance, but chrome steel usually provides stronger bearing fatigue performance in non-corrosive environments.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The correct industry terminology includes: AISI 420 stainless steel balls, AISI 420A stainless steel balls, AISI 420B stainless steel balls, hardened martensitic stainless steel balls, magnetic stainless steel balls and corrosion-resistant hardened stainless steel balls.<\/p>\n\n\n\n<h2 id=\"technical-specifications\" class=\"wp-block-heading\">Especificaciones t\u00e9cnicas<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Parameter<\/strong><\/td><td><strong>Typical SDBALLS Supply Range \/ Note<\/strong><\/td><\/tr><tr><td>Material<\/td><td>AISI 420A \/ AISI 420B<\/td><\/tr><tr><td>Steel Family<\/td><td>Martensitic stainless steel<\/td><\/tr><tr><td>Di\u00e1metro<\/td><td>0.5 mm &#8211; 300.00 mm;other sizes subject to production confirmation<\/td><\/tr><tr><td>Grado de precisi\u00f3n<\/td><td>G20, G40, G80, G100, G200, G500, G1000; selected according to application and cost target<\/td><\/tr><tr><td>Dureza<\/td><td>HRC 48-58 typical after hardening;final range confirmed by material grade, size and process<\/td><\/tr><tr><td>Densidad<\/td><td>Approx. 7.7-7.8 g\/cm3 reference value<\/td><\/tr><tr><td>Magnetismo<\/td><td>Magnetic\/ ferromagnetic<\/td><\/tr><tr><td>Tratamiento t\u00e9rmico<\/td><td>Hardened; passivation available \/ commonly supplied for stainless applications<\/td><\/tr><tr><td>Resistencia a la corrosi\u00f3n<\/td><td>Moderate corrosion resistance; suitable for water, steam, oil and petrol contact in many applications; not recommended for strong acid, chloride, seawater or highly corrosive environments<\/td><\/tr><tr><td>Acabado superficial<\/td><td>Polished, passivated, oiled or customized surface treatment upon request<\/td><\/tr><tr><td>Packing<\/td><td>Bulk bag, carton, drum, pail, pallet or customized OEM packing<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 id=\"chemical-composition-reference\" class=\"wp-block-heading\">Chemical Composition Reference<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The following ranges are reference values for material selection and webpage information. Final chemical composition should follow the agreed material standard, mill certificate and purchase order requirement.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Calificaci\u00f3n<\/strong><\/td><td><strong>C %<\/strong><\/td><td><strong>Si % max<\/strong><\/td><td><strong>Mn % max<\/strong><\/td><td><strong>P % max<\/strong><\/td><td><strong>S % max<\/strong><\/td><td><strong>Cr %<\/strong><\/td><\/tr><tr><td>AISI 420A \/ 420J1 reference<\/td><td>0.16-0.25<\/td><td>1.00<\/td><td>1.00<\/td><td>0.040<\/td><td>0.030<\/td><td>12.00-14.00<\/td><\/tr><tr><td>AISI 420B \/ 420J2 reference<\/td><td>0.26-0.35<\/td><td>1.00<\/td><td>1.00<\/td><td>0.040<\/td><td>0.030<\/td><td>12.00-14.00<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 id=\"international-grade-equivalents\" class=\"wp-block-heading\">International Grade Equivalents<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">International equivalence should always be confirmed against the customer drawing or purchase standard, because local standards and carbon ranges may vary. The following table is for buyer reference.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>SDBALLS Product Grade<\/strong><\/td><td><strong>Common International Reference<\/strong><\/td><td><strong>Typical Description<\/strong><\/td><\/tr><tr><td>AISI 420A<\/td><td>EN 1.4021 \/ X20Cr13; JIS SUS420J1; GB\/T 20Cr13<\/td><td>Lower-carbon martensitic stainless steel, hardenable, moderate corrosion resistance<\/td><\/tr><tr><td>AISI 420B<\/td><td>EN 1.4028 \/ X30Cr13; JIS SUS420J2; GB\/T 30Cr13<\/td><td>Higher-carbon 420-type martensitic stainless steel, higher hardness than 420A<\/td><\/tr><tr><td>AISI 420C<\/td><td>EN 1.4034 \/ X46Cr13; JIS SUS420J2 type depending on standard<\/td><td>Higher-carbon 420 family grade, used when higher hardness and wear resistance are required<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 id=\"heat-treatment-hardness-performance\" class=\"wp-block-heading\">Heat Treatment, Hardness &amp; Performance<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">AISI 420A\/420B balls are hardened martensitic stainless steel balls. Heat treatment increases hardness and wear resistance, making them suitable for rolling contact and mechanical components where a non-hardened 300-series stainless ball would be too soft.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Typical hardness for SDBALLS AISI 420A\/420B stainless steel balls is HRC 48-58. Exact hardness depends on material grade, ball diameter, heat treatment process and customer specification. For applications requiring higher hardness and stronger wear performance, buyers may consider AISI 420C or AISI 440C stainless steel balls. For applications requiring stronger corrosion resistance instead of hardness, AISI 304, AISI 316 or 316L stainless steel balls may be more suitable.<\/p>\n\n\n\n<h2 id=\"applications-application-fit\" class=\"wp-block-heading\">Applications &amp; Application Fit<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">AISI 420A\/420B stainless steel balls are suitable for mechanical and industrial applications where a hardened stainless surface, magnetic behavior and moderate corrosion resistance are required.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Solicitud<\/strong><\/td><td><strong>Fit Level<\/strong><\/td><td><strong>Why It Fits<\/strong><\/td><td><strong>Buyer Note<\/strong><\/td><\/tr><tr><td>Special bearings<\/td><td>Bien<\/td><td>Hardened martensitic stainless steel offers wear resistance and moderate corrosion resistance<\/td><td>Confirm load, speed, lubrication and corrosion environment<\/td><\/tr><tr><td>Automotive safety belt components<\/td><td>Bien<\/td><td>Commonly used in mechanical locking and movement components requiring consistent ball quality<\/td><td>Confirm grade, diameter tolerance and surface finish<\/td><\/tr><tr><td>Special pumps and valve-related parts<\/td><td>Bien<\/td><td>Suitable for water, oil and petrol contact in many mechanical systems<\/td><td>For chemical, seawater or chloride media, consider 316\/316L or ceramic alternatives<\/td><\/tr><tr><td>Lighters and ballpoint pens<\/td><td>Very good<\/td><td>Hard polished stainless surface supports small mechanical movement and wear resistance<\/td><td>Confirm miniature size and surface appearance requirements<\/td><\/tr><tr><td>Industrial hardware and mechanical assemblies<\/td><td>Bien<\/td><td>Balanced hardness, magnetic properties and moderate stainless corrosion resistance<\/td><td>Confirm whether 420A\/420B hardness is sufficient<\/td><\/tr><tr><td>Food-contact or highly hygienic applications<\/td><td>Limited \/ application-dependent<\/td><td>420 is stainless but martensitic and magnetic; corrosion resistance is lower than 304\/316<\/td><td>Use 304\/316 when food-contact corrosion resistance is the priority<\/td><\/tr><tr><td>Marine, acidic or chloride environments<\/td><td>Not recommended<\/td><td>420A\/420B is not designed for aggressive corrosion exposure<\/td><td>Consider 316\/316L, ceramic or other corrosion-resistant materials<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 id=\"material-selection-guide\" class=\"wp-block-heading\">Material Selection Guide<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Material Option<\/strong><\/td><td><strong>Typical Strength<\/strong><\/td><td><strong>Limitation<\/strong><\/td><td><strong>When to Recommend<\/strong><\/td><\/tr><tr><td>AISI 420A\/420B stainless steel balls<\/td><td>Hardened martensitic stainless, HRC 48-58, moderate corrosion resistance<\/td><td>Lower hardness and wear resistance than 420C\/440C; lower corrosion resistance than 304\/316<\/td><td>Special bearings, pumps, lighters, ballpoint pens, safety belt components and general stainless mechanical use<\/td><\/tr><tr><td>AISI 420C stainless steel balls<\/td><td>Higher hardness and wear resistance in the 420 family<\/td><td>Still not as corrosion resistant as 304\/316 in aggressive media<\/td><td>When 420A\/420B performance is not enough and higher hardness is required<\/td><\/tr><tr><td>AISI 440C stainless steel balls<\/td><td>High hardness, strong wear resistance and precision bearing suitability<\/td><td>Higher cost; corrosion resistance still limited in chloride\/marine environments<\/td><td>Precision stainless bearings, valves, ball screws and demanding wear applications<\/td><\/tr><tr><td>AISI 304\/304L stainless steel balls<\/td><td>Better general corrosion resistance, non-hardened, usually non-magnetic or slightly magnetic<\/td><td>Lower hardness and wear resistance<\/td><td>Food, cosmetic, general corrosion-resistant and non-hardened stainless applications<\/td><\/tr><tr><td>AISI 316\/316L stainless steel balls<\/td><td>Stronger corrosion resistance, especially in many chemical or chloride-related environments<\/td><td>Lower hardness; higher cost<\/td><td>Marine, chemical, food and high-corrosion applications<\/td><\/tr><tr><td>AISI 52100 chrome steel balls<\/td><td>High hardness and strong bearing performance in non-corrosive conditions<\/td><td>Not stainless; requires rust protection<\/td><td>Precision bearings, motors and high-fatigue non-corrosive applications<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 id=\"manufacturing-process-control\" class=\"wp-block-heading\">Manufacturing &amp; Process Control<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">SDBALLS controls hardened martensitic stainless steel ball production through raw material selection, wire drawing, cold heading, flashing, heat treatment, grinding, lapping or polishing when required, cleaning, passivation or oil protection when specified, final inspection and export packing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For AISI 420A\/420B balls, heat treatment and surface finishing are especially important because they influence hardness, wear behavior, corrosion resistance and final appearance. For precision or OEM projects, SDBALLS can discuss material certificates, hardness targets, grade requirements, surface finish, inspection reports and customized packing before production.<\/p>\n\n\n\n<h2 id=\"quality-control-inspection\" class=\"wp-block-heading\">Quality Control &amp; Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Typical inspection items for AISI 420A\/420B stainless steel balls include diameter, grade, roundness, surface appearance, hardness, material confirmation, magnetic behavior, corrosion-related surface condition, packing condition and batch traceability.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For OEM and industrial buyers, SDBALLS can support sample approval, inspection reports, PPAP-style documents, third-party testing, RoHS requests, customized labels and batch-based quality documentation when required.<\/p>\n\n\n\n<h2 id=\"packing-options\" class=\"wp-block-heading\">Packing Options<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">AISI 420A\/420B stainless steel balls can be supplied in bulk bags, cartons, plastic pails, steel drums, palletized export packing or customer-specific OEM packing. Packing can be adjusted according to ball diameter, unit weight, surface protection requirement, shipping method and customer warehouse handling preference.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For polished or passivated stainless steel balls, clean handling, moisture control and anti-scratch packing should be confirmed before production when surface appearance is important.<\/p>\n\n\n\n<h2 id=\"how-to-specify-for-quotation\" class=\"wp-block-heading\">How to Specify for Quotation<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">To quote accurately, please confirm: material grade (AISI 420A or AISI 420B), diameter in mm or inch, precision grade, required hardness, surface finish, passivation or oil protection requirement, quantity, packing method, target application, inspection documents, destination port and trade term.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For replacement projects, buyers are encouraged to provide drawings, current supplier specification sheets, photos, samples, hardness requirements, working environment and any corrosion or wear problems found in current use.<\/p>\n\n\n\n<h2 id=\"technical-faq\" class=\"wp-block-heading\">Technical FAQ<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: What are AISI 420A\/420B stainless steel balls?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A: They are hardened martensitic stainless steel balls used when buyers need a combination of hardness, wear resistance, magnetic properties and moderate corrosion resistance.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: Are AISI 420A\/420B balls magnetic?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A: Yes. AISI 420A\/420B stainless steel balls are martensitic stainless steel balls and are magnetic \/ ferromagnetic.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: What hardness can SDBALLS supply for AISI 420A\/420B stainless steel balls?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A: Typical hardness is HRC 48-58 after hardening. The final hardness range should be confirmed according to material grade, diameter and application requirement.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: What is the difference between AISI 420A\/420B and AISI 420C stainless steel balls?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A: AISI 420A\/420B balls are selected when the required hardness and wear resistance are lower than 420C. AISI 420C is normally recommended for higher hardness and stronger wear performance within the 420 stainless family.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: Are AISI 420A\/420B stainless steel balls corrosion resistant?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A: They offer moderate corrosion resistance and can be used in many applications exposed to water, steam, oil or petrol. They are not recommended for strong acid, chloride, seawater or highly corrosive environments.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: Can AISI 420A\/420B balls replace AISI 304 or 316 stainless steel balls?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A: Only when hardness and wear resistance are more important than maximum corrosion resistance. For food, marine, chemical or high-corrosion environments, AISI 304, 316 or 316L stainless steel balls may be more suitable.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>P: \u00bfQu\u00e9 grados de precisi\u00f3n est\u00e1n disponibles?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A: SDBALLS can supply common grades including G20, G40, G80, G100, G200, G500 and G1000. The best grade depends on application, motion smoothness, tolerance requirement and cost target.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: What information is needed for a quotation?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A: Please provide material grade, diameter, precision grade, hardness requirement, surface finish, quantity, packing, application, inspection requirement, destination and trade term.<\/p>","protected":false},"excerpt":{"rendered":"<p>Proporciona una dureza moderada con buena resistencia a la corrosi\u00f3n, lo que la hace adecuada para aplicaciones industriales y mec\u00e1nicas en general.<\/p>","protected":false},"featured_media":3808,"parent":0,"menu_order":5,"template":"","meta":{"_acf_changed":true,"_gspb_post_css":"","_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kad_post_transparent":"default","_kad_post_title":"","_kad_post_layout":"fullwidth","_kad_post_sidebar_id":"","_kad_post_content_style":"unboxed","_kad_post_vertical_padding":"hide","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":""},"product-category":[4],"class_list":["post-176","product","type-product","status-publish","has-post-thumbnail","hentry","product-category-stainless-steel-ball"],"acf":[],"taxonomy_info":{"product-category":[{"value":4,"label":"Stainless Steel Ball"}]},"featured_image_src_large":["https:\/\/sdballs.com\/wp-content\/uploads\/2026\/02\/image1-2-1024x683.png",1024,683,true],"author_info":[],"comment_info":"","_links":{"self":[{"href":"https:\/\/sdballs.com\/es\/wp-json\/wp\/v2\/product\/176","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sdballs.com\/es\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/sdballs.com\/es\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/sdballs.com\/es\/wp-json\/wp\/v2\/media\/3808"}],"wp:attachment":[{"href":"https:\/\/sdballs.com\/es\/wp-json\/wp\/v2\/media?parent=176"}],"wp:term":[{"taxonomy":"product-category","embeddable":true,"href":"https:\/\/sdballs.com\/es\/wp-json\/wp\/v2\/product-category?post=176"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}