金属资料系列冲击试验与高温脆性(国外英文资料).docVIP

金属材料系列冲击实验与低温脆性(国外英文资料) Metal material series impact experiment and low temperature brittleness Chen guotao wood: 095One, the purpose of the experiment To understand the characteristics of material toughness and the effect of impact test on material toughness test. By measuring the impact of low carbon steel, industrial pure iron and T8 steel at different temperatures, the metal toughness and brittle transformation characteristics were observed. To study the method of measuring the temperature of the brittle transition temperature of low carbon alloy steel, and by combining the combination of the summer ratio shock experiment to find the brittle factors that reduce the metal toughness. Second, the experimental principle The principle of metal summers shock experiment The summer ratio shock experiment is to have the test specimen of the shape, size and the type of the gap, and put it on the sample pedestal of the impact tester, and put it in the state of the simple support beam. Then with provisions of the height of the pendulum to a one-time sample, essentially it is through the process of energy conversion, measuring the broken specimen under the impact of shock absorption function. The potential difference of the shock absorber in the test is shown below: AK = A - A1 A = FH1 = FL1 - cosine alpha A = FH2 = FL1 - cosine beta A - the starting position of the pendulum. A1 - strike the position of the sample. If the energy loss such as air resistance and friction is not considered, the absorption work of the sample will be: AK = F times L (cosine beta minus cosine alpha) F -- the gravity of the pendulum, N; L - pendulum length (the distance between the center of the pendulum and the center of gravity), mm; Alpha - the maximum Angle that the pendulum raises before the shock. Beta - the maximum Angle that the pendulum raises after the shock. The steel brittle transition temperature principle Brittle fracture is a kind of rapid fracture, the break process absor