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Influence of nonmetallic inclusions on the resistance of metal weld to brittle fractures
Authors: Boldyrev A.M., Orlov A.S., Guschin D.A., Rubtsova E.G., Sannikov V.G.
Number of views: 274
According to statistics, up to 80% of all fixed metal structure accidents are associated with welded joints. However, most of the emergency destructions, usually caused by non-metallic inclusions in the weld metal, are fragile. The probability
of brittle fracture decreases with increasing plasticity. And plasticity, that depends on the mobility of dislocations to a great degree, decreases with temperature decrease and increase in the strain rate. The plasticity of the metal is a tructurally
sensitive property and depends on the type of crystal lattice that determines the number of densely packed directions and slip planes. Low-alloy steels, mainly used in welded steel structures, have a volume-centered cubic lattice with a relatively small number of planes and sliding direction.