High-speed steel hob ion nitriding method and tool

Abstract

The invention discloses a high-speed steel hob ion nitriding method and tool. The high-speed steel hob ion nitriding tool comprises an insulation mica base, a glow screen, an upper anti-nitriding sleeve, and a lower anti-nitriding sleeve. The high-speed steel hob ion nitriding method comprises following steps: step one, installing; step two, nitriding; and step three, disassembling. The provided method and tool can prevent over-nitriding of handles on two ends of a hob, thus the precision and hardness of the handles are guaranteed; the excess nitriding of the tool nose is avoided, high currentdensity is prevented, high temperature of local parts of the tool nose is prevented, the hardness of the tool nose is guaranteed, and the yield is increased.

Description

technical field [0001] The invention relates to the field of ion nitriding of high-speed steel hobs, in particular to a method and tooling for ion nitriding of high-speed steel hobs. Background technique [0002] Ion nitriding is a chemical heat treatment method for nitriding by glow discharge caused by a high-voltage electric field in a dilute nitrogen-containing gas. It is a special ion nitriding furnace, in a low vacuum state, the workpiece is used as the cathode and the furnace wall is used as the anode to connect high-voltage direct current, so that the gas in the furnace is transformed into a plasma state, and the nitrogen-containing plasma continuously bombards the surface of the workpiece to make it Heating, at the same time, some nitrogen atoms penetrate into the surface of the workpiece to achieve the effect of nitriding. [0003] After the vacuum degree of the vacuum chamber is evacuated to 66.67Pa, the high voltage is connected, and a small amount of ammonia gas...

AI Technical Summary

Problems solved by technology

[0004] The tip of the high-speed steel hob is prone to tip discharge and glow concentration during ion nitriding, and it is difficult to heat up; the use of ordinary low-frequency power supply is easy to arc and cause damage to the tip of the knife. The temperature of the tip part is too high, resulting in a decrease in hardness

After nitriding, the surface of high-speed steel is easy to form a compound layer, which will increase the brittleness and cause the hob to chip during use.

[0005] If the handles at both ends of the high-speed steel hob are nitrided, it will cause volume expansion and lower precision

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