{"id":1051,"date":"2026-07-03T09:03:24","date_gmt":"2026-07-03T09:03:24","guid":{"rendered":"https:\/\/www.wudejiansteel.com\/?p=1051"},"modified":"2026-07-03T09:03:26","modified_gmt":"2026-07-03T09:03:26","slug":"what-mold-steel-should-be-used-for-injection-molding-40-fiber-pps-molds-made-of-h13-and-2344-are-not-durable-blog-207","status":"publish","type":"post","link":"https:\/\/www.wudejiansteel.com\/?p=1051","title":{"rendered":"What mold steel\u00a0should be used for injection molding 40-fiber PPS? Molds made of H13 and 2344 are not durable.blog\u00a0207"},"content":{"rendered":"\n

During the 297th live stream, a viewer asked what mold steel<\/strong>\u00a0to use for injection molding 40% fiber-reinforced PPS. They noted that H13, even after heat treatment to increase hardness, is not durable, and the same applies to 2344.<\/p>\n\n\n\n

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H13 and 2344 are 4Cr5MoSiV1 medium-carbon steels with a carbon content of 0.38%. Their hardness is only 50 HRC. While they have good toughness, their wear resistance is too poor. They cannot withstand the erosion caused by 40% fiber-reinforced plastic on the mold, which will quickly wear the mold down, resulting in flash on the product.<\/p>\n\n\n\n

 Based on past feedback from users, when using H13 or 2344 with 40% glass-fiber-reinforced compounds, the injection molding cycle life does not exceed 100,000 cycles before flash begins to appear on the products. For 40% glass-fiber-reinforced PPS, depending on the performance requirements of the mold and based on past successful cases, I recommend using 8503 as the core material for its non-stick properties.<\/p>\n\n\n\n

 8503 has a hardness of 55\u201361 HRC and twice the toughness of DC53. Compared to DC53, its performance doubles without doubling the price, while also offering the added benefit of non-stick properties. In particular, these non-stick properties, combined with its high hardness, provide a fundamental and effective solution to the problem of molds being worn down by high-glass-fiber-content materials, which leads to flash on the products.<\/p>\n\n\n\n

As Mr. Yu from Zhejiang puts it, using 8503 with 30% glass-fiber-reinforced nylon compound works exceptionally well\u2014even with continuous molding, there\u2019s no flash. Additionally, Mr. Wan reported that using 8503 with a 30% glass-fiber-reinforced nylon compound resulted in a mold life of 1 million cycles.<\/p>\n\n\n\n

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Regarding the 40% glass-filled PPS mentioned by the user, neither H13 nor 2344 mold steels are durable enough for this application. For the mold cavity, you should use the non-stick 8503 steel; for the core, tilting pins, and inserts\u2014which require exceptionally high toughness\u2014you can use high-toughness LG mold steel<\/strong>.<\/p>\n\n\n\n

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We have a client who injection molds 30% glass-filled PC. He originally used Japanese-imported DHA1 mold steel, but could only produce 50,000 parts before the mold cavity surfaces became rough, resulting in poor surface finish on the molded products. He now uses 8503 (non-stick grade) for the mold cavity material and high-toughness LG for the cores and tilt pins. He has been using this combination for the past 2\u20133 years.<\/p>\n\n\n\n

\u00a0The mold supervisor told me that using 8503 for the cavity inserts ensures the mold cavities won\u2019t become rough, the parting lines won\u2019t be eroded, and the mold\u2019s service life is guaranteed. For mold inserts, wear resistance is the primary consideration, so non-stick\u00a08503 mold steel<\/a><\/strong>\u00a0is sufficient. However, for cores, inclined ejectors, and small bosses, I use LG steel for insert machining. LG has 8 to 9 times the toughness of DC53, with a hardness of 54\u201358HRC, It\u2019s so tough that it won\u2019t break even if you bend it with a hammer; it won\u2019t fracture when used as a core, ensuring high toughness without being worn away. By using this combination, I\u2019ve reduced my mold costs. The molds last longer and require fewer repairs, so it\u2019s cost-effective for me.<\/p>\n\n\n\n

\u00a0In response to the user\u2019s question about injection molding 40% glass-filled PPS: using H13 or 2344, even after heat treatment and hardening, results in poor durability. I recommend using 8503 non-stick material for the mold inserts. For molds with fine slanted ejectors and cores, use high-toughness LG mold steel<\/a><\/strong>.<\/p>\n\n\n\n

 If you\u2019re currently using H13, 2344, SKD61, or even S136 for molds that process glass-filled materials, the molds are prone to wear, and the products will quickly develop flash. You might want to try the non-stick 8503 mold steel<\/strong>.<\/p>\n\n\n\n

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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":"

During the 297th live stream, a viewer asked what mold steel\u00a0to use for injection molding 40% fiber-reinforced PPS. They noted that H13, even after heat treatment to increase hardness, is not durable, and the same applies to 2344. H13 and 2344 are 4Cr5MoSiV1 medium-carbon steels with a carbon content of 0.38%. Their hardness is only […]<\/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-1051","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