Partial tempering method for carburized and hardened parts

Abstract

Abstract PURPOSE:To temper only the carburized layers of carburized and hardened parts in a short time by heating only the carburized layers to a specified temp. by high frequency induction heating and cooling the heated layers. CONSTITUTION:Each of carburized and hardened parts 5 each consisting of a carburized layer 5a and a core part 5b is set so that the part A to be tempered is positioned close to a high frequency induction heater 1. A high frequency current having about 500-2,000Hz is supplied to the heating coil 2 of the heater 1 to heat the part A to a temp. close to the A3 transformation point such as 730-760 deg.C. After heating the part A for a prescribed time, cooling water is spouted from the cooling water spouting holes 3 to cool the part A, and heat treatment is completed. By always feeding cooling water or the like to a pipe 4 for cooling the heating coil 2, the seizing of the coil 2 is prevented. Thus, only the carburized layer 5a is well tempered, and the hardness of the core part 5b is not reduced.

Inventors

• 👤 Kazuo Uno
• 👤 宇野　和夫
• 👤 Kenji Kashihara
• 👤 樫原　賢二

Bibliographic Details