Introduction to Several Surface Treatment Processes for Investment Casting

Introduction to Several Surface Treatment Processes for Investment Casting

The surface treatment of precision castings is a process method of artificially forming a surface layer on the substrate material that has different mechanical, physical, and chemical properties from the substrate. The purpose of surface treatment is to meet the corrosion resistance, wear resistance, decorative or other special functional requirements of the product. For metal castings, the commonly used surface treatment methods include mechanical polishing, chemical treatment, surface heat treatment, and spray coating. Surface treatment refers to cleaning, cleaning, removing burrs, oil stains, and oxide scales on the surface of the workpiece. Today, we will introduce the surface treatment processes for castings.

1、 Polishing

Polishing refers to the process of using mechanical, chemical, or electrochemical forces to reduce the surface roughness of a workpiece, in order to obtain a bright and flat surface. It is the process of modifying the surface of a workpiece using polishing tools and abrasive particles or other polishing media.

2、 Electroplating

Electroplating is the process of using the principle of electrolysis to deposit a thin layer of other metals or alloys on certain metal surfaces. It is a process that uses electrolysis to attach a metal film to the surface of metal or other material components, thereby preventing metal oxidation (such as rust), improving wear resistance, conductivity, reflectivity, corrosion resistance (such as copper sulfate), and enhancing aesthetics.

3、 Sandblasting

The sandblasting process uses compressed air as the power to form a high-speed jet beam, which sprays materials and other materials at a high speed onto the surface of the workpiece to be treated, causing changes in the appearance of the outer surface of the workpiece. Due to the impact and cutting effects of abrasives on the workpiece surface, the workpiece surface obtains a certain degree of cleanliness and different roughness, improving the mechanical properties of the workpiece surface.

4、 Oxidation

Oxidativeness refers to the ability of a substance to acquire electrons. Substances in high valence states and active non-metallic elements (such as fluorine, chlorine, oxygen, etc.) generally have oxidizing properties. The oxidation treatment of metals is the formation of a protective oxide film on the metal surface by reacting with oxygen or oxidants to prevent metal corrosion.

Precision machining