이종재료 스테인리스강(STS304) / 연강(SS400)의 GTAW용접 특성에 관한 연구

Abstract

There is a growing application of non-ferrous materials in terms of development of engineering technology, diversification of the material environment and cost reduction. However, by welding of the same metal it may not be able to meet the change of the material. Therefore, study of the dissimilar metal welding is required. GTAW(Gas Tungsten Arc Welding) is a welding that melts the basic metal and filler metal by generating tungsten electrodes and arc among inert gas atmospheres and using arc heat. GTAW process becomes necessary in various industries such as plant and ship because it can obtain high quality welding and demanding is increasing. In this research the experiment was made by classifying material into the same(STS304+STS304, SS400+SS400) and different(STS304+SS400) kind with choosing a cold strip stainless steel sheet(STS304) and a general structural rolled steel material(SS400). Under welding condition of 12~16V, 115~180A, picking a test piece was performed by Gas Tungsten Arc Welding using Φ2.4㎜ TIG wire. Using mechanical properties through tensile test and hardness test, results about the same and different material are followed below:

1) Welding the different metal STS304 and SS400 was successful, and the expansion experiment by Gas Tungsten Arc Welding brought about the cutting face in tensile test is shown in the region of HAZ(Heat affected zone) of SS400.

2) Hardness was the highest in welded metal of STS304+SS400 and hardness of STS400 HAZ was higher than SS400.

3) STS304 and SS400 will be profited from considering mechanical property and price with use condition.