Of Er, Zn, And Compressional Deformation Of Mg-0.6zr Alloy Mechanical Performance And Damping Behavior

In this thesis Mg-0.6Zr alloy is investigated for mechanical and damping properties through alloying,hot extruding,and annealing.The strengthening and damping mechanism are deeply analyzed by means of OM,DMA,TEM and SEM.The K-G-L model is introduced to study the correlation of the damping-frequency and damping-Strain amplitude. Experiment results are obtained as follows.1,It can be observably refined of the microstructure by added 0.6 %Er and 1%Zn in the Mg-0.6Zr alloy.The second phase of Mg-Er, Mg-Zn and Mg-Er-Zn,about 0.1μm,is distributed discontinuous nearby the boundary.It can slow down the dendrite to grow up in solidification process,and nail the boundary and dislocation in other process.So the cast Mg-0.6Zr-0.6Er-1Zn alloy has been thinned down to 60μm.And after extruded in 280℃,the grain size of Mg-0.6Zr-0.6Er-1Zn alloy decrease to 6μm.And the degree of grain-growth of the Mg-0.6Zr-0.6Er-1Zn alloy is less than the Mg-0.6Zr alloy after extrusion in 400℃.2,Because of strengthening effect of solid-solution,grain-refining, and the second phase,theσ_b,σ_0.2and elongation of the Mg-0.6Zr-0.6Er-1Zn alloy was above 198.8MPa,83.0MPa,and 22.5%.After homogenized and extruded in 280℃(λ=25),theσ_b,σ_0.2and elongation of the alloy increased to 232.5 MPa,147.8 MPa and 23.3%.The mechanical properties of the alloys have been increased in various degrees.3,The internal friction behavior of the Mg-0.6Zr alloys was researched.The results show that Mg-0.6Zr alloys' damping behavior can be explained by the K-G-L model.In the low-frequency condition,damping-frequency behavior is shown as linear correlation under low strain amplitude;and it is nearly irrespective as static-delay type under high strain amplitude.There is rather pertinent about damping-strain amplitude capacities that the damping capcity is improved by the increase of strain amplitude in 10 Hz frequency condition.