The Storage Effects On Stainless Steel And Peek And Its Mechanism

The storage effect of 0Cr18Ni9 steel, 0Cr17Ni4Cu4 Nb steel and PEEK used for kinematic pair were studied by simulating the 1:1 natural storage. The quality of samples, surface nano-hardness and the roughness of surface were mesured. Surface morphology, chemical composition and organizational structure were analyzed by means of scanning electron microscopy(SEM), scanning atomic force microscopy(AFM), X-Ray photoelectron spectroscopy and fourier transform infrared spectroscopy analyzer(FTIR) in order to explore the storage effect and its mechanism.The results showed that, the storage process of two kinds of metal of 0Cr18Ni9 steel and 0Cr17Ni4Cu4 Nb steel leaded to the quality increase and the nano-hardness of the surface increase, too. The change of surface roughnes of two kinds of materials and the growth pattern of its sediments were different.The surface roughness of 0Cr18Ni9 steel increased with time going on. However, the surface roughness of 0Cr17Ni4Cu4 Nb steel decreased. The reason of the difference was the different growing pattern. The column sediments on 0Cr18Ni9 stainless steel surface were of uniform growth. But, the sediments on 0Cr17Ni4Cu4 Nb stainless steel surface were the preferential growth of the large size sediment, and fine sediments grew uniformly along the surface. The content ratio of O-C=O and C-O of 0Cr18Ni9 steel increasesd linearly along with storage process. But, the content ratio of O-C=O and C-O of 0Cr17Ni4Cu4 Nb steel decreasesd linearly.In the process of storage, the quality of PEEK decreased, but the nano-hardness of the surface increased. Storage leaded to the formation of cluster and columnar sediment on the PEEK surface. The sediments grew slowly and some of them connected with each other. Gradually, the sediments covered the surface scratches, resulting in the surface roughness decreased. By XPS analysis, a new structure of O-C=O was introduced into the PEEK surface. And the content of C-C decreased, while the content of C-O and O-C=O increased slowly, and the content of C in PEEK matrix was significantly lower than that of the original surface.