Steel selection that affects the life of plastic injection moulds

Plastic injection mold according to different service life and accuracy requirements, plastic mold prices are also different. Different plastic mold steel in addition to the cost of the steel itself is different, different quality hardness of steel, processing the same precision required tools and processes are also different.

Plastic injection mold is divided into five levels according to the service life, the requirements for steel:

Plastic injection moulds are generally divided into five levels according to their service life. More than 1 million times at level 1, 500,000 to 1 million times at level 2, 300,000 to 500,000 times at level 3, 100,000 to 300,000 times at level 4, and below 100,000 times at level 5.

Both primary and secondary dies require heat treatment. Hardness of about HRC50 steel, not easy to wear, injection products will not be out of whack. Therefore, the selected steel should not only have good heat treatment properties, but also be easy to work in the case of good high hardness. There are other considerations, of course.

8407, S136 in Sweden, 420, H13 in the United States, 2316,234,083 in Europe, or SKD61, DC53 in Japan (originally metal mold material, used in special cases). Highly corrosive plastics are generally selected S136, 2316,420 and other steel, weakly corrosive plastics in addition to S136, 2316,420, SKD61, NAK80, PAK90, 718M. The appearance requirements of the product also have a great impact on the choice of plastic die steel material. Transparent parts and products requiring mirror surfaces include S136, 2316, 718S, NAK80, PAK90 and 420. The plastic injection mold with high transparency should choose S136, followed by 420.

The three level molds are S136H, 2316H, 718H, 083H, hardness HB270-340.

Cheap P20,718, 738, 618, 231,2711 for grade 4 and 5 low life plastic molds. For molds with very low requirements, S50C and 45# steel can also be used directly on the cavity of the mold embryo.