TIG용접에 의한 TI합금의 AM에서 Interpass Peening에 따른 기계적 성질의 변화

Abstract

Ti alloys are very high specific strength and are mainly used in aircraft parts and mainly produced the parts by machining. However, due to the high yield strength and risk of fire, it is difficult to cut. Therefore manufacturing cost increase in proportion to cutting amount. Recently metal additive manufacturing has being developed on Ti parts in order to minimize the cutting amount Metal additive manufacturing can be classified into powder based and wire based. The wire based AM, which can be deposited at a high deposition rate of more than 1kg/hr, is applied to large and simple shape of parts. However, due to epitaxial grain growth, large columnar grains grown to z axis direction are formed. The large columnar grains make mechanical properties of z axis direction decrease as compared with x axis direction. In this study on metal AM, in order to improve the mechanical properties of Ti alloy by TIG welding, peening were applied after every deposition of layer by layer. As a result, through interpass peening, the mechanical properties in both the x and z axis directions are improved, it is possible to achieve the same level as the case of comparing the mechanical properties of the x and z axis and can be solved the anisotropy of the material.