| Welding cold-rolled steel to cast iron
Dear Elmer: Is there a way to weld 1018 cold-rolled steel to cast iron? If so, how? James Dear James: You can weld 1018 low-carbon steel to cast iron using shielded metal arc welding (SMAW) and a nickel-based ENiFe electrode. Clean the surfaces before you start. If the joint is highly restrained or if the casting is thick, you might need to preheat the casting. Preheating reduces the cooling rate, residual stress, distortion, and the tendency for cracking. Use short stringer beads. Don't overheat the base metal. The maximum interpass temperature is 600 degrees F. Peening sometimes is used to relieve stress if cracking is a problem. Peening is a mechanical working of metals using impact blows. Peening while the weld deposit is still warm (or as it cools) can help to improve the properties of the deposit and help refine the metallurgical structure. It also assists in relieving shrinkage stresses and in correcting distortion. Peening works the metal and expands it, which counteracts the shrinkage (which causes the cracking) that occurs or may occur during the cooling. | | ||||||
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Introduction The colour formed when stainless steel is heated, either in a furnace application or in the heat affected zone of welds, is dependent on several factors that are related to the oxidation resistance of the steel. The heat tint or temper colour formed is caused by the progressive thickening of the surface oxide layer and so, as temperature is increased, the colours change. Oxidation resistance of stainless steels However, there are several factors that affect the degree of colour change and so there is no a single table of colour and temperature that represents all cases. The colours formed can only be used as an indication of the temperature to which the steel has been heated. Factors affecting the heat tint colours formed Steel composition The chromium content is the most important single factor affecting oxidation resistance. The higher the chromium, the more heat resistant the steel and so the development of the heat tint colou...
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