Static axial tension tests of 50MPa concrete specimens were conducted to obtain the tensile stress-strain relationship curves and compared them with those of 30MPa concrete.The test results indicated that high strength concrete and normal concrete has a similar tensile stress-strain relationship curves in shape,however,as the compressive strength of concrete increase,the tensile strength increase correspondingly and it becomes more brittle.
Sputtered NiTi shape memory alloy(SMA) thin film for microactuator was studied.The processes of fabrication and texture that affect structure and transformation characteristics of thin films were investigated.Microdevice based on SMA thin film was fabricated,and its deformation behavior was analyzed.The results show that the crystallized NiTi thin films with a strong texture of A(110) can be sputter-deposited by in situ heating;The NiTi beam shows a recovering ratio of 0.76% due to the existence of texture.
