718H High Polishing Plastic Mould Steel Plate Pre-Hardened for High Gloss Plastic Moulds

718H plastic mould steel plate is a high-performance pre-hardened mould material engineered for high-quality plastic moulds that demand excellent surface finish, toughness, and dimensional stability. As an upgraded version of general plastic mould steel, 718H plastic mould steel plate contains nickel, chromium, and molybdenum alloys, which enhance hardenability, toughness, and polishing performance, making it the preferred choice for high-gloss household appliances, automotive interiors, cosmetic packaging, and electronic housing moulds. Unlike ordinary mould steels, 718H plastic mould steel plate can achieve mirror polishing without pores or pinholes, ensuring flawless surface quality for finished plastic products.
Manufactured using advanced smelting technology and controlled rolling processes, our 718H plastic mould steel plate features a dense and uniform internal structure with low impurities and fine grain size. This structural advantage greatly improves the material’s resistance to deformation during machining and long-term usage. The pre-hardened hardness of 33–38 HRC provides excellent wear resistance and structural stability, allowing the mould to withstand continuous injection cycles without premature wear or cracking. Additionally, 718H plastic mould steel plate demonstrates outstanding welding performance, enabling convenient repair and modification of mould cavities without affecting overall hardness or stability.
Our 718H plastic mould steel plate is available in a full range of thicknesses from 10mm to 300mm, catering to both small precision moulds and large-scale automotive or appliance mould bases. The material’s excellent machinability allows for efficient CNC milling, grinding, and EDM processing, significantly reducing production time and tooling costs. We offer customized cutting, precision grinding, and heat treatment stabilization services to ensure each plate meets strict dimensional and flatness requirements. For manufacturers pursuing high-quality plastic moulds, 718H plastic mould steel plate delivers a perfect balance of performance, reliability, and cost-efficiency, supporting long mould life and consistent production of high-quality plastic components.