The selection of materials for precision metal parts is very rich. Different materials are matched according to the precision requirements, application scenarios, and performance needs of the parts. They can be mainly divided into the following categories:
Basic General-Purpose Metal Materials
Stainless Steel: Common grades include SUS303 and 304. It is rust-resistant, wear-resistant, and has good dimensional stability. It is a common choice for medical devices, precision bearings, and instrument accessories. However, it is prone to tool sticking during machining and requires a special cooling process.
Free-Machining Steel: Typical grades include 12L15 and 10S20 low-carbon free-machining steel. Sulfur is added to optimize chip breaking, resulting in high machining efficiency and low thermal deformation. It is suitable for mass production of small to medium-sized precision turned parts and standard connectors.
Aluminum Alloy: Represented by 6061 and 7075, it has outstanding lightweight advantages. 6061 is easy to machine and is widely used in 3C products and aerospace structural components; 7075 has higher strength and can withstand certain loads, making it the first choice for high-load lightweight parts.
Copper Alloy Materials
Leaded Brass: Grades such as HPb63-3, C31000, and C3604 exhibit excellent machinability and are often used as benchmarks for the machinability of copper alloys. They produce easily broken chips and exhibit low tool wear, making them a core material for watch gears, electronic connectors, and instrument movements.
Beryllium Copper: After aging, its strength can reach 1000-1380 MPa, approaching that of medium-strength steel. It combines elasticity and fatigue resistance, and is widely used in high-end precision elastic components and connector terminals.
Pure Copper (Red Copper): Possesses excellent electrical and thermal conductivity, with a conductivity reaching 100% IACS, making it suitable for precision conductive parts requiring high conductivity.
