High carbon steel tool steel

High carbon steel is often called tool steel, the carbon content from 0.60% to 1.70%, can be quenched and tempered. Hammers, crowbars, etc. are made of steel with 0.75% carbon content; Cutting tools such as drills, taps, reamers, etc. are manufactured from steel with a carbon content of 0.90% to 1.00%.

Properties of high carbon steel

Advantages:

1. High hardness (HRC60-65) and good wear resistance can be obtained after heat treatment.

2. annealing state moderate hardness, with good machinability.

3. easy access to raw materials, low production costs.

Welding process of high carbon steel

1. when the mass fraction of high carbon steel carbon is greater than 0.60%, the hardening and crack sensitivity tendency after welding is greater, so the weldability is very poor and can not be used to manufacture welding structures. It is often used to manufacture parts and parts that need more hardness or wear resistance, and its welding work is mainly welding repair.

2. because the tensile strength of high carbon steel is mostly above 675MPa, the commonly used electrode model is E7015, E6015, and E5016 and E5015 electrodes can be selected when the component structure is not high. In addition, chromium-nickel austenitic steel electrode can also be used for welding.

3. Welding process

(1) Because high-carbon steel parts in order to obtain high hardness and wear resistance, the material itself needs to be heat treated, so it should be annealed before welding.

(2) The welding should be preheated before welding, and the preheating temperature is generally above 250 ~ 350 ° C, and the interlayer temperature must be kept not lower than the preheating temperature during the welding process.

(3) After welding, the welds must be kept warm and cooled slowly, and immediately sent into the furnace for stress relief heat treatment at 650℃.

4. high carbon steel carbon content is relatively high, weldability is relatively poor, welding to preheat, after welding to slow cooling or 350 degrees of low temperature tempering treatment, the length of the specific heat treatment is determined by the thickness of the workpiece. If it cannot be preheated, it is necessary to use welding materials with good welding performance and good crack resistance, but the welding speed must be reduced.

5. high carbon steel belongs to the class of poor welding performance, if you want to weld, should be welded under preheating conditions, after welding must be stress relief heat treatment.