In the manufacturing of mechanical parts, generally, the blank is generated by forming technologies such as casting, forging, welding and cutting, and then processed by machining such as cutting and grinding, and finally the product meeting the design requirements and shape is obtained. In this process, the consumption of materials, energy and time is very large, and a large amount of waste chips, waste liquid and noise pollution will be produced.

Precision forming technology is a process technology that directly produces the shape or dimensional accuracy of the final part by using physical and chemical changes such as melting, crystallization, plastic deformation, diffusion and other deformation, combined with new materials, modern die technology and computer numerical simulation technology. Precision forming can not only improve the utilization rate of materials, save energy, shorten processing time and reduce pollution, but also make component materials obtain chemical composition and microstructure that are difficult to obtain by traditional methods, so as to improve the quality and performance of products.

Precision forming technology has been widely used in industrial developed countries. Through cooperation with advanced process equipment and detection means, precision forming manufacturing units of different grades have been formed, and the traditional forming processes and equipment have been generally replaced. According to the prediction of the international Machining Technology Association, in the next ten years, the combination of precision forming and grinding will replace the cutting of most small and medium-sized parts.

Precision forming technology mainly includes liquid metal precision solidification forming and solid metal precision plastic forming. Due to the limitation of professional ability and space, the author only introduces the dieless casting technology in the precision solidification of liquid metal and the precision forging technology in the precision plastic forming of solid metal.