How to Choose the Best Nitrided Screw Manufacturer for Long-Lasting Performance
In the world of plastic extrusion and injection molding, the screw is the primary engine of production. While various advanced coatings have emerged, the nitrided screw remains the industry's reliable workhorse due to its balance of cost and surface hardness. However, not all nitrided screws are created equal. In 2026, as manufacturers push for higher efficiency and use more recycled resins, choosing the right nitrided screw manufacturer can be the difference between a machine that runs for years and one that fails in months. The Science of Surface Hardness The "nitriding" process is a thermo-chemical heat treatment that diffuses nitrogen into the surface of the steel. This creates a hard, wear-resistant "case" while keeping the core of the screw tough and ductile. The chemical reaction typically involves the dissociation of ammonia at high temperatures: $$2NH_3 \rightarrow 2N + 3H_2$$ The nascent nitrogen ($N$) then penetrates the metal to form iron and alloy ...