| On base of a series of investigation and study, many defaults have been found in traditional process of picks. Aim of the subject is to offer production method of picks which can not only hold strength and ductility of solder joint, pick and carbide tip, but also improve hardness and wear-resistance around carbide tip effectively.Coal cutting mechanism of picks has been analyzed and the stress of pick has also been calculated making use of Ansys. Results show that the stress is the biggest and degree of wear is the heaviest near pick head, which leads to inactivation. We make use of plasma-jet surface metallurgy to improve process of picks. New process has been made as following: baiting→ forging→machining→plasma-jet surface metallurgy→heat treatment→finishing blind hole→ cold-charging carbide tip→antiseptic treatment.Fe-based alloy coating has been obtained which is bonded with substrate metallurgically. Microstructure and performance have been tested and analyzed. Results show that (Fe,Cr,W,Nb)7C3 is dispersing in γ-Fe(Cr,W,Nb,Al). The characteristic of the microstructure is that its hardness is higher and its wear-resistance is better, which can protect carbide tip from abscission effectively.According to principle of strengthening and toughening of metal, material of picks has been improved which use 20CrMnTi. After heat treatment lath martensite is obtained which owns higher strength and toughness. This kind of material can adapt to working condition of picks.Coal charging carbide tip can erase harmful effects of braze welding.36 picks have been made according above process to test under well. Results show that longevity of picks improves largely. Picks produced by new process will own large market.
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