Manufacture method for superfine hard alloy blind hole bars

Abstract

The invention relates to a manufacture method for superfine hard alloy blind hole bars. Soft straight-hole superfine hard alloy bar billets are manufactured in an extruding forming mode, soft solid bar billets are manufactured in an extruding or mould pressing mode, the diameter of each soft solid bar billet is smaller than that of a straight hole of each soft straight-hole superfine hard alloy bar billet, the shrinkage coefficient of each soft solid bar billet is smaller than that of each soft straight-hole superfine hard alloy bar billet, the soft solid bar billets are cut off according to the fixed length, then put into the hole at one end of each soft straight-hole bar billet to be fixed, placed into a low-pressure sintering furnace to be sintered, the holes of the soft straight-hole bar billets are larger than the shrinkage coefficient of each soft solid bar billet in during sintering, prestress produced in the sintering process enable the soft straight-hole bar billets and the soft solid bar billets to be densified through metallurgical bonding, and the superfine hard alloy blind hole bars different in diameter and depth are manufactured. The manufactured superfine hard alloy blind hole bars are used for manufacturing automobiles and aviation machinery and non-standard and efficient hard alloy overall inner-cooling drill bits for machining other mechanical device parts.

Description

technical field [0001] The invention relates to a method for preparing an ultrafine cemented carbide blind hole rod. The ultrafine cemented carbide blind hole rod prepared by the method can be used to manufacture non-standard, High-efficiency solid carbide drills. Background technique [0002] Drilling is the most common process on modern automatic processing lines or machining centers. The drill bit is a common tool for drilling. During use, due to the large force it bears, it is prone to heat and wear, especially at the top of the tool tip. [0003] In order to prolong the service life of the drill bit, a series of methods are used, the most common is the external cooling process. However, under this process, due to the continuous discharge of debris during processing, it is difficult for the coolant to reach the top, and the ideal cooling effect cannot be achieved. As the processing depth and difficulty increase, the effect envisaged by this cooling process becomes mor...

AI Technical Summary

Problems solved by technology

However, in recent years, with the increasing drilling efficiency, drilling depth and drilling quality, straight hole internal cooling drills gradually cannot meet the performance requirements of high-efficiency hole processing for drills.

In order to meet the drilling requirements of deep holes and special holes and improve the efficiency of chip removal, various types of side hole internal cooling tools have been designed. The traditional production method of this tool is to use the solid ultra-fine carbide rod with EDM The processing method is to drill a certain depth of internal cooling blind hole first, and then make the tool by opening the inner hole on the side according to the need. Since the blind hole of this type of drill bit is deep, the production efficiency of blind hole processing by EDM is extremely low and wastes materials. , the size of the product is not easy to control, and the yield is low; the second is to plug one end of the ultra-fine cemented carbide rod with a straight hole with other materials to form a blind hole. This method uses heating to melt other materials to plug the hole , because cemented carbide is a brittle material, it is easy to form thermal cracks when heated, and the bonding state between the plugging material and the cemented carbide rod is not easy to accurately grasp, which affects the improvement and promotion of the service life of this type of drill application

Images