Study On The Mould Design And Forming Experiment Of Squeeze Casting Hammerhead Used On Hammer Crusher

With the highly development of basic industries, the service conditions of hammerhead on hammer crusher are becoming much worse. Common castings have been unable to satisfy the higher requirements at present while a series of questions were uncovered in traditional sand casting process. In order to solve the questions uncovered, squeeze casting technique used as the process for critical steel castings of hammerhead was put forward in this paper. In this study, high manganese steel (ZGMn13) which is the common material for hammerhead is used as the research material, hammerhead on hammer crusher with different size through squeeze casting were used as examples. The technique was studied systemically through experiments and theories in the following aspects: choices of production process, mold design, process design, control of the quality, microstructure of the formed parts and their mechanical properties etc.Firstly, two kinds of squeeze casting process were made against the 5kg hammerhead: direct squeeze casting and indirect squeeze casting; process of squeeze casting of bimetal hammer was made against the 50kg hammerhead. Process design and mould design were made for the previous three kinds of squeeze casting process.Secondly, experiments of direct squeeze casting and squeeze casting of bimetal hammer were performed here.Under the direct squeeze casting, the suitable process parameters are obtained: pouring temperature is 1420℃, the forming pressure is among 258MPa, holding time of 10s. Under these processing parameters, the grain size of the hammer is 5 grade. Impact toughness of it is 2091.7 kJ/m~2. Compared to the hammerhead produced under sand casting, its impact toughness raised about 17%. Meanwhile, the crack, cold lap and shrinkage depression on the hammer was studied here.In the squeeze casting experiment of bimetal hammer, we made hammers under those process parameters: pouring temperature is 1480℃, the forming pressure is among 200MPa, holding time of 180s. We focused on the coextrusion process here. Meanwhile, equipment for study the work hardening property, imitating the real work condition is made here. Using this equipment, conclusions were made as follows: The work hardening property of high manganese steel hammerhead produced under squeeze casting is better than that of permanent mould cast hammerhead.