{"id":1076,"date":"2026-07-06T09:06:32","date_gmt":"2026-07-06T09:06:32","guid":{"rendered":"https:\/\/www.wudejiansteel.com\/?p=1076"},"modified":"2026-07-06T09:06:33","modified_gmt":"2026-07-06T09:06:33","slug":"when-punching-0-12-0-2-red-copper-with-a-tin-coating-the-skh-9-high-speed-steel-developed-burrs-after-only-20000-punches-which-is-highly-unusual-blog-212","status":"publish","type":"post","link":"https:\/\/www.wudejiansteel.com\/?p=1076","title":{"rendered":"When punching 0.12\u20130.2 red copper with a tin coating, the SKH-9 high-speed steel developed burrs after only 20,000 punches, which is highly unusual.blog\u00a0212"},"content":{"rendered":"\n

0.12\u20130.2 thick tin-plated red copper, using SKH-9 high-speed steel<\/a><\/strong>. Currently, after 20,000 production cycles, the punch and cutting edge show wear at the R-corner, causing burrs. What type of die steel <\/strong>would be better? Question from a viewer during Live Stream #297<\/p>\n\n\n\n

 There are two types of wear: one is friction wear caused by insufficient wear resistance, which typically occurs only after a certain number of products have been produced. This is easy to resolve; simply selecting a mold steel <\/strong>with better wear resistance will extend the mold\u2019s service life.<\/p>\n\n\n\n

 The other type is adhesive wear caused by material adhesion, which occurs shortly after the mold is put into use. It generally happens during the stamping of soft materials; even though the material you\u2019re using appears hard, it may still lack sufficient wear resistance. This is typically caused by segregation defects in the mold steel,<\/strong> resulting from microscopic cracks in the microstructure that are invisible to the naked eye. This issue can be resolved by selecting mold steel <\/strong>with high-quality smelting.<\/p>\n\n\n\n

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 This user is stamping 0.12\u20130.2 mm-thick red copper. This material is very soft and thin, so in theory, it shouldn\u2019t be difficult to stamp. Furthermore, SKH-9 is a high-speed steel with a hardness of HRC 62\u201364, which already offers excellent wear resistance. However, after stamping only 20,000 parts, the cutting edge has worn down and developed burrs\u2014this is a classic case of adhesive wear caused by material sticking.<\/p>\n\n\n\n

 Since copper is not a hard material, the die does not need to be overly hard; the key is its non-stick properties. Given the current situation\u2014where the SKH-9 die developed burrs after only 20,000 stampings\u2014there are three solutions:<\/p>\n\n\n\n

 First, apply a surface coating to the existing SKH-9 die to improve surface finish and cover any microcracks. This is a cost-effective measure that can significantly extend the die\u2019s service life.<\/p>\n\n\n\n

\u00a0If you wish to change the die steel, you can switch to 8566 die steel<\/a>.<\/strong>\u00a0There are already successful case studies of 8566 being used for stamping copper, and since its price is comparable to SKH-9, your material costs will not increase.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Mr. Wu was stamping 0.3-mm copper inserts on a high-speed press. The Cr12MoV<\/strong> punch was not wear-resistant and developed burrs after only a few stamping cycles. Due to the high stamping speed and frequent die changes, the customer was very dissatisfied. However, after switching to 8566, the punch was able to withstand over 1 million stamping cycles, producing more than 100,000 units per day, and lasted for about 10 days. The customer reported that the results were very good.<\/p>\n\n\n\n

 Third option: If you\u2019re concerned that 8566 isn\u2019t wear-resistant enough, you can choose PM23 powdered high-speed steel<\/strong>, with a hardness of HRC 64\u201366. It utilizes an advanced powder metallurgy process that avoids the segregation issues commonly found in high-speed steel. Therefore, when punching copper with PM23, copper powder won\u2019t stick to the punch. Moreover, its hardness is higher than SKH-9, and its wear resistance is better than SKH-9, making it very effective. However, it costs twice as much as SKH-9, so you\u2019ll need to consider the cost implications.<\/p>\n\n\n\n

Based on the user\u2019s mold operating conditions, I provide three solutions for them to choose from to help resolve their pressing steel selection issues\u2014that\u2019s my daily work.<\/p>\n\n\n\n

 *************<\/p>\n\n\n\n

Wu Dejian’s\u00a0tool\u00a0steel<\/a><\/strong>, the chief of staff of the user, bought everything he had used.<\/p>\n","protected":false},"excerpt":{"rendered":"

0.12\u20130.2 thick tin-plated red copper, using SKH-9 high-speed steel. Currently, after 20,000 production cycles, the punch and cutting edge show wear at the R-corner, causing burrs. What type of die steel would be better? Question from a viewer during Live Stream #297  There are two types of wear: one is friction wear caused by insufficient […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1076","post","type-post","status-publish","format-standard","hentry","category-blog"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t