The Development Of High-Carbon Chromium Welding Electrode Used For Overlaying Welding With Low Cost,High Hardness And Good Abrasion Resistance

Nowadays, has developed a variety of wear-resistant materials used for overlaying welding in China and the abroad, although these electrodes can meet the requirements in terms of wear resistance, but it has defects about the cost, process and environment. If choose simple high-carbon Fe-Cr casting iron alloy system, will obtain higher hardness of overlaying welding alloy, but because of the high-carbon, leads to the deterioration of the its crack resistance. For this reason, to develop new overlaying welding materials has important engineering application value, which with high hardness, good crack and abrasion resistance, but low cost. The article bases on the principle of reducing cost and choose simple alloy system, by the method of electric arc overlaying welding, through add Si?B?Mn?Ti and other alloy element, reduce temperature change point of martensite in overlaying welding layer since these alloy elements, so that to develop one kind of new Fe-Cr-B-C overlaying welding electrode with high hardness, good crack and abrasion resistance.Firstly, to calculate additive amount of alloy elements preliminary, to optimize mineral composition of electrode covering, the test researched the effects of different mineral composition with slag detachability, spatter, dust amount, overlaying welding layer forming of the electrode, got the best comprehensive performance of coating formula, through orthogonal experiment of alloy elements, got the best formula, for the overlaying welding layer, performed experiment about hardness, abrasion, metallographic, scanning electron microscope, XRD diffraction, mechanical property, crack, and heat resistance.The research shows:influence of alloy elements with overlaying welding metal hardness: The first is ferrochromium, then carborundum, boron carbide, minimum is graphite, matrix structure of overlaying welding is mainly martensite and retained austenite, hard phase is mainly Fe-Cr?M23?C, B?₆?Ti₂B?Fe₃C and B₄C which has high micro-hardness, overlaying welding layer has good crack resistance, Crack test no preheating before welding, not slow cooling after welding conditions after penetrating inspection found no crack, surfacing layer crack resistance is good, overlaying welding layer still remains high hardness after heating In a certain temperature range.