Evaluation of cracking on the surface of gas fuel filter housing

摘要

The purpose of shaping products using plastic working methods is to give a material the desired shape by generating the appropriate plastic deformations without breaking the cohesion. Shaping of products from aluminum and its alloys poses many technological difficulties despite the fact that it has been commonly applied for a long time. Various defects of cold-worked products very frequently appear under industrial conditions. Loss of cohesion or cracking are particularly dangerous defects. In modern technology, non-conventional processes that ensure achievement of high dimensional accuracy and minimal material losses during post-machining are employed. By using cold plastic working processes precise products or products with nearly no allowance for machining are manufactured, i.e. "net shape" or "near net shape" products. Metals are significantly hardened during cold plastic working processes leading to a gradual reduction of capacity for plastic deformation. During shaping of fuel gas filter housing two simultaneous processes are involved: - combined extrusion, in which metal flows in two directions: forward (shaping of the connector pipe) and reverse (tube shaping);;non-uniform tri-axial compression enabling conservation of material cohesion are present in this process;;-flanging of the tube rim during the final stage of the extrusion;;tensile stresses fostering