氧化物之助銲劑對SUS 304不□鋼電漿銲道穿深能力之研究

Abstract

本研究目的主要在探討氧化物型助銲劑對沃斯田鐵系不□鋼的銲件銲道熔透深度與機械性質之影響。本實驗選用SUS 304不□鋼為試驗材料，採電漿電弧銲(PAW)為銲接方式。助銲劑選用Cr2O3、Fe2O3 、MnO2、MoO3、SiO2、TiO2、ZnO七種氧化物粉末。試驗時將活性助銲劑均勻塗在母材欲銲接之部位上，並採用直接對母材施以銲接方式進行。 實驗結果顯示:(1) 各種氧化物型助銲劑均可有效提高銲道穿深能力，在熱輸入量高時有顯著的高深寬比值。(2) 以SiO2助銲劑所進行的PAW-flux製程，銲道穿深能力及深寬比值最優且效果最好。(3) 若考慮氧化物型助銲劑對不□鋼銲道熔融面積之實驗結果，以MnO2銲道所形成的熔融面積最小。(4) 電漿電弧柱收縮與陽極斑點收縮現象的共同作用應是活性助銲劑可有效提高銲道穿深能力的主要因素。(5) 不同成份的助銲劑並不會對SUS 304不□鋼的微硬度值和極限抗拉強度產生顯著的改變。

The purpose of this research is to study the effect of adding oxide flux on the weld penetration and mechanical property of austenitic stainless steels. This experimentation is to select the SUS 304 stainless steel weldment using plasma arc welding (PAW) process. The fluxes included Cr2O3,Fe2O3,MnO2,MoO3,SiO2, TiO2 and ZnO. Active flux was smeared over the weldment well mixed with bead-on-plate method. The results show:(1) All of seven active fluxes can increase weld penetration and depth/width ratio effectively, especially for high energy. (2) The flux SiO2 is the best of seven fluxes according to the weld penetration and depth/width ratio during PAW-flux process. (3) The flux MnO2 is the smallest of seven fluxes according to the fusion zone. (4) The contractions of both plasma arc and anode spot are the reasons of deep penetration of fusion zone with the use of flux. (5) The influence of adding flux into the weldment on the mechanical properties is not significant.