A martensitic stainless steel Welding Electrodes stainless steel containing chromium 5 to 9 percent of chromium steel and high chromium steel containing 12% chromium. Such steel hardened tendency of large, easy to produce high hardness of martensite and bainite to the fragility, the residual stress, prone to cold cracks in the weld. Therefore, general welding must be performed before the warm-up and the interlayer insulation, has not yet cooled high-temperature tempering after welding. , 13 chrome stainless steel welding: the welding of such chromium steel sclerosing large, easy to crack, the use of similar chromium stainless Nickel Electrode(CHK202, CHK207) welding to be carried out more than 300 ℃ preheat and post weld 700 ℃, tempering the slow cooling treatment. Weldments after welding can not be carried out, the application of a chromium stainless steel electrode (CHS107, CHS207) welding. 3, 17 chrome stainless steel welding: These chrome steel is usually to improve the corrosion resistance and weldability and add the right amount of stable element titanium, niobium, molybdenum, can be weldability compared with 13 chromium steel of the same type can be used chrome Stainless steel electrodes (CHK302, CHK307) welding. Before welding, the weldment should be about 200 ℃ preheating, about 800 ℃ tempering after welding. Also can be chrome-nickel stainless steel electrode (such as CHS107 CHS207), post-weld heat treatment.
Thorium-tungsten electrode is the earliest use of rare earth tungsten pipe clamping, and so far the best welding performance tungsten stainless steel clamps, therefore, on a global scale, the variety of tungsten electrode market share of the highest, but because the thorium-tungsten electrode grinding and polishing powder metallurgy and rolling radioactive contamination will occur in the process, Europe and the United States to limit the production of the varieties electrode, but because of its excellent welding performance, its use is not restricted.
Thorium-tungsten electrodes containing thorium oxide (Th02 or thorium oxide), it is the most common tungsten electrode in the United States, has become a standard to judge other tungsten electrode is good or bad. However, due to the tungsten electrode low-level radioactive hazards, many users have switched to other options. Overall, 2% of the thorium-tungsten electrode is a tungsten electrode, with the lowest work function, even in overload voltage to perform well. Thorium tungsten electrode performance in many ways better than pure tungsten electrodes. Thorium oxide to provide the current carrying capacity of about 20 percent higher than that of pure tungsten and generally longer life, but also help to prevent the contamination of the welding time. Use of thorium-tungsten electrode, the arc starting is easier, more stable arc than pure tungsten electrodes or zirconium tungsten electrode. Thorium-tungsten electrode 1% (EWTh - 1) and thorium-tungsten electrode can be used for DCEN is 2% (EWTh - 2). They the tip of the welding process to maintain the sharpened, which can be used to welded steel pipe, usually without direct current, because the ball without cracking it difficult to maintain a state-of-the-art welding, which the DC is a must.