Method for enhancing service life of cold-stamping mould of automobile by composite coating

Abstract

The invention provides a method for enhancing the service life of a cold-stamping mould of an automobile by a composite coating. The method is characterized by comprising the following steps: firstly,carrying out polishing treatment on the surface of a cast iron mould; afterwards, precipitating the composite coating on the surface of the cast iron mould by chemical reduction, wherein a basal bodyof the composite coating is Ni-p alloy, 5-20% of spherical particle with nano level size is evenly distributed in an alloy layer, and the spherical particle is nano level artificial diamond or fullerene granules; and then, carrying out polishing treatment on the surface of the cast iron mould. The invention adopts the flexible grinding and polishing of the surface of the mould until a mirror faceis smooth, so that the service life of the mould can be enhanced, the smoothness degree of a stamping workpiece is enhanced, and the napping phenomenon of the surface of the workpiece is reduced. Thecomposite coating is precipitated by chemical reduction, the wear resistance of the mould is increased, the stamping frequency of the cast iron mould reaches 8-10 ten thousand times, and the phenomena of tension fracture, napping and scratch formed on the surface of the stamping workpiece are avoided.

Description

technical field

[0001] The invention relates to a method for improving the service life of a composite coating on the surface of an automobile cold stamping die. Background technique

[0002] Carbon is one of the most abundant elements on the earth. Materials composed of a single carbon element have greatly different properties due to their different structures. Graphite with a hexagonal planar structure is extremely soft. Diamond, which has an equiaxed cubic structure, is the hardest mineral in the world. Fullerene (ball) is a newly discovered allotrope of the third type of carbon, usually a completely symmetrical hollow carbon sphere composed of 60 carbon atoms, with good symmetry, like a modern football. Under normal conditions, C60 fullerenes (spheres) are as soft as graphite, but when squeezed to 70% of their original volume, they are harder than diamond. After the extrusion force is removed, it can be elastically deformed to return to its original shape. This is a s...