Is there any requirement for the hardness of parts in precision machining

Usually metal processing, or hardware processing, is a special mechanical equipment, work is also convenient, and much faster than manual work. Assuming that there is no mechanical equipment, the number of manual work can not keep up with the usual expansion, usually mechanical equipment can be said that various industries have been popularized, such as packer, packaging machine, folding machine, crane, forklift, etc And other equipment, in the usual can be said to use like flow!
When the material is stopped, the material is not enough. If it is not enough, the parts that will be processed will not meet the needs of the mechanical equipment. Because of this, the demand for material request is awesome when the processing time is stopped.
Assuming that the processing of metal materials is stopped, then it depends on its hardness. Among many metal materials, stainless steel is hard, followed by cast iron. The hardness of copper is lower than that of cast iron, while the hardness of aluminum is low. Therefore, stainless steel should be selected when the hardness of workpiece is high, and aluminum should be selected when the hardness is low.