The optimum coating composition of alkali Fe powder welding rods was designed by orthogonal experiment with mix rates. A new kind of effective RE-Fe powder welding rod was prepared which could be used at the condition...The optimum coating composition of alkali Fe powder welding rods was designed by orthogonal experiment with mix rates. A new kind of effective RE-Fe powder welding rod was prepared which could be used at the condition of direct and indirect current. The arc characteristics and stabilities of effective Fe powder welding rods containing RE were analyzed by HANNOVER analyzer. The efficiency of Fe powder welding rods was tested by weighting method. It was found that the stability of Fe powder welding rods was improved when it was added with rare earths. The results of impact experiment at low temperatures and SEM analysis on impact break showed that the grain was refined, the welding joint was cleaned, and the mechanical properties of joint was enhanced with proper RE content. It was provided with good processing property for this effective RE-Fe powder welding rod, and its efficiency could arrive at 180%.展开更多
The influence mechanism of light rare earth elements, which are transited to the welding seam of low-alloy high strength (LAHS) steel through the covering of t he electrode, on the toughness of the welding seam was s...The influence mechanism of light rare earth elements, which are transited to the welding seam of low-alloy high strength (LAHS) steel through the covering of t he electrode, on the toughness of the welding seam was studied. The experimental results show that proper amount of rare earth elements can desulfurate, dehydro genate, reduce inclusions and purify the structure of the welding seam. Rare ear th element additions have the effect on welding seam and, at the same time, the transformation of side-batten ferrite is resisted while the pin-ferrite s tructure is promoted. The improvement of the toughness of the welding seam is du e to the purifying action of rare earth elements as well as their refining effec t on the structure. However, the toughness of the welding seam can decrease whe n the amount of light rare earth elements are added excessively because the crys tal grains become coarser, porosities appear and the inclusions increase as well . The experimental results show that the suitable amount of light rare earth ele ment additions is about 2%.展开更多
文摘The optimum coating composition of alkali Fe powder welding rods was designed by orthogonal experiment with mix rates. A new kind of effective RE-Fe powder welding rod was prepared which could be used at the condition of direct and indirect current. The arc characteristics and stabilities of effective Fe powder welding rods containing RE were analyzed by HANNOVER analyzer. The efficiency of Fe powder welding rods was tested by weighting method. It was found that the stability of Fe powder welding rods was improved when it was added with rare earths. The results of impact experiment at low temperatures and SEM analysis on impact break showed that the grain was refined, the welding joint was cleaned, and the mechanical properties of joint was enhanced with proper RE content. It was provided with good processing property for this effective RE-Fe powder welding rod, and its efficiency could arrive at 180%.
文摘The influence mechanism of light rare earth elements, which are transited to the welding seam of low-alloy high strength (LAHS) steel through the covering of t he electrode, on the toughness of the welding seam was studied. The experimental results show that proper amount of rare earth elements can desulfurate, dehydro genate, reduce inclusions and purify the structure of the welding seam. Rare ear th element additions have the effect on welding seam and, at the same time, the transformation of side-batten ferrite is resisted while the pin-ferrite s tructure is promoted. The improvement of the toughness of the welding seam is du e to the purifying action of rare earth elements as well as their refining effec t on the structure. However, the toughness of the welding seam can decrease whe n the amount of light rare earth elements are added excessively because the crys tal grains become coarser, porosities appear and the inclusions increase as well . The experimental results show that the suitable amount of light rare earth ele ment additions is about 2%.