With the development of society and economy, the process of industrial modernization is accelerating, and people’s requirements for mechanical design are increasing day by day. In the design of mechanical products, how to select the appropriate material according to the design needs is very critical. Generally speaking, the materials commonly used in mechanical equipment are steel, cast iron, non-ferrous metal and non-metallic materials, etc. The following is a brief overview of the basic requirements that need to be considered in the selection of materials in the design of mechanical products.
1. Functional requirements
Meeting the functional requirements of the product is the most basic principle and starting point for the selection of materials. The so-called product functional requirements refer to the parts made of selected materials that can work normally under given working conditions and within a predetermined life period. And different mechanical parts products, their focus is different. For example, when the parts are under heavy load and require light weight and small size, materials with higher strength can be selected; parts that work under sliding friction should choose materials with good anti-friction properties; parts that work at high temperatures should choose heat-resistant materials ; When subjected to static stress, plastic or brittle materials can be selected; when subjected to impact loads, materials with better impact toughness must be selected.
2. Manufacturing technique requirements
Mainly refers to the requirements of material blank manufacturing (casting, forging, cutting plate, cutting rod), machining, heat treatment, surface treatment and so on. The so-called process requirements refer to the selected materials with good cold and hot processing properties and good heat treatment processability. For example, castings should be used for parts with complex structure and mass production, and forgings or weldments should be used for single-piece production. For simple disc-shaped parts (such as gears or pulleys, etc.), whether the blanks are castings, forgings or weldments mainly depends on their size, structural complexity and batch size; for single-piece small batch production, weldments should be used. ; Small size, large batch, simple structure, die forgings should be used; complex structure, mass production, castings should be used.
3. Appearance requirements
The goal of product appearance design is to visualize the process of product functions, functions, etc., to give products a three-dimensional appearance, exquisite external dimensions, and product operation interfaces to meet users’ aesthetic and operational requirements. In the design of mechanical products, the selection of materials should fully consider the appearance of the product, and try to meet the requirements of the product in terms of appearance.
4. Cost requirements
Low comprehensive cost is the ultimate goal of all products. Therefore, when selecting parts materials, materials that can meet the above requirements and are cheap should be selected as much as possible. Not only the price of the material, but also the processing cost and maintenance cost, the utilization rate of the material, the substitute material, etc. should be considered, that is, the comprehensive economic benefit should be considered.
In the design of mechanical products, the principle of practicality should be adhered to when selecting materials. The type of materials should be determined according to the specific requirements of the parts. At the same time, it should be ensured that the materials are harmless to the human body and the environment. Moreover, the load type of the material should be fully considered, and the cost should be reduced as much as possible on the premise of ensuring the design quality.
