{"id":1683,"date":"2026-10-14T08:57:43","date_gmt":"2026-10-14T08:57:43","guid":{"rendered":"https:\/\/www.wudejiansteel.com\/?p=1683"},"modified":"2026-10-14T08:57:44","modified_gmt":"2026-10-14T08:57:44","slug":"is-corrosion-on-the-pa66gf30-injection-mold-core-causing-flash-s136-and-dc53-are-both-the-wrong-choices-8503-mold-steel-can-handle-1-million-cycles-blog-330","status":"publish","type":"post","link":"https:\/\/www.wudejiansteel.com\/?p=1683","title":{"rendered":"Is corrosion on the PA66+GF30 injection mold core causing flash? S136 and DC53 are both the wrong choices; 8503 mold steel\u00a0can handle 1 million cycles. Blog 330"},"content":{"rendered":"\n

Case Study: After a Six-Month Trial Period, the Customer Placed a Bulk Order for 23 Pieces of 8503 Mold Steel<\/a><\/strong><\/p>\n\n\n\n

This morning\u2019s most significant order: Mr. Zhang, who injection molds PA66+GF30, placed a single order for 23 pieces of 8503 mold steel<\/strong> in four different specifications, moving from a trial period to bulk purchasing.<\/p>\n\n\n\n

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Mr. Zhang added me as a friend in September 2020 and contacted me on March 6 of this year, asking, \u201cThe mold inserts corrode after a short period of use. What mold steel do you recommend?\u201d<\/p>\n\n\n\n

After further discussion, it became clear that he was injection molding a generic brand of nylon reinforced with 30% glass fiber. He had originally used heat-treated S136 and DC53 hard mold steel for the mold inserts, but the molds would develop flash after producing only a small number of parts\u2014flash appeared on the product\u2019s outer diameter, and the mold surface showed obvious signs of being \u201ceaten away.\u201d<\/p>\n\n\n\n

Analysis of the Failure Cause: Why couldn\u2019t S136 and DC53 eliminate the flash?<\/p>\n\n\n\n

Conclusion first: Injection molding PA66+GF30 (30% glass fiber content) causes severe mold erosion; the mold steel must simultaneously meet the requirements of \u201chigh wear resistance + non-stick properties.\u201d S136 and DC53 each lack one of these properties, so both were incorrect material choices.<\/p>\n\n\n\n

Materials<\/strong><\/strong><\/td>Composition\/Hardness<\/strong><\/strong><\/td>The Problem<\/strong><\/strong><\/td><\/tr>
S136<\/td>4Cr13 stainless steel, C \u2248 0.38%, approx. 50 HRC  <\/td>It has good toughness but poor wear resistance; it cannot withstand glass fiber erosion, causing the mold core to be \u201ceaten away,\u201d resulting in flash on the product.<\/td><\/tr>
DC53<\/td>High-carbon cold-work steel, C \u2248 1.0%, 60\u201362 HRC<\/td>It is wear-resistant but exhibits severe segregation, with a large number of microscopic cracks in the microstructure that are invisible to the naked eye; adhesive wear occurs between the glass fibers and these microcracks, which also leads to chipping.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

In a nutshell: S136 is tough but lacks wear resistance, while DC53 is wear-resistant but prone to microcracks\u2014neither material is suitable for GF30 reinforced plastic applications.<\/p>\n\n\n\n

Solution: 8503 Non-Stick Mold Steel<\/p>\n\n\n\n

8503 is a proprietary non-stick mold steel developed by Wudejian Mold Steel. Key specifications:<\/p>\n\n\n\n

Item<\/strong><\/strong><\/td>Specifications<\/strong><\/strong><\/td><\/tr>
Hardness<\/td>55\u201361 HRC<\/td><\/tr>
Toughness<\/td>Twice that of DC53<\/td><\/tr>
Key Features<\/td>Non-stick + High hardness<\/td><\/tr>
Value for Money<\/td>Offers twice the performance of DC53 at the same price, plus the added benefit of non-stick properties<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Mechanism of Action: Non-stick properties combined with high hardness provide a fundamental and effective solution to the problems of \u201cmolds with high glass fiber content being eroded, product flash, and mold surface roughness.\u201d<\/p>\n\n\n\n

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 Industry Validation: Feedback from Boss Wan\u2014Nylon + 30% glass fiber; 8503 withstood 1 million cycles without issues; Mr. Yu from Ningbo commented: \u201cUsing 8503 for glass-fiber-reinforced molds is really nice\u2014it keeps molding without any flash!\u201d<\/p>\n\n\n\n

  Customer Validation Process: From a single trial set to a bulk purchase of 23 pieces<\/p>\n\n\n\n

1. March of this year: Mr. Zhang purchased one set of 8503 mold steel<\/strong> to test;<\/p>\n\n\n\n

2. Over the following six months: He gradually ordered additional pieces, continuing to validate its performance during use;<\/p>\n\n\n\n

3. Today, six months later: He placed a single order for four specifications, totaling 23 pieces, marking the transition to bulk purchasing.<\/p>\n\n\n\n

The fact that the customer is willing to purchase in bulk demonstrates that 8503\u2019s performance has successfully resolved his mold flash issues\u2014this is a more powerful endorsement than any advertisement.<\/p>\n\n\n\n

 Conclusion<\/p>\n\n\n\n

When injection molding high-glass-fiber-reinforced plastics such as PA66+GF30, the logic for selecting mold steel is: a base material with high wear resistance to prevent material sticking. S136 lacks sufficient wear resistance, while DC53 suffers from microcrack-induced adhesive wear\u2014both will be \u201cworn down\u201d by the glass fibers. The 8503 mold steel<\/strong>, with its non-stick properties, high hardness of 55\u201361 HRC, and twice the toughness of DC53, is the fundamental solution to flash issues. This has been validated by a customer who has achieved 1 million mold cycles and placed repeat bulk orders.<\/p>\n\n\n\n

*************<\/p>\n\n\n\n

Wu Dejian\u2019s <\/strong>tool\u2002steel<\/strong><\/a>, the chief of staff of the user, bought everything he had used.<\/p>\n","protected":false},"excerpt":{"rendered":"

Case Study: After a Six-Month Trial Period, the Customer Placed a Bulk Order for 23 Pieces of 8503 Mold Steel This morning\u2019s most significant order: Mr. Zhang, who injection molds PA66+GF30, placed a single order for 23 pieces of 8503 mold steel in four different specifications, moving from a trial period to bulk purchasing. Mr. Zhang […]<\/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-1683","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