The Study On Surface State And Mechanical Property Of 0Cr17Ni7Al Steel And HPb63-3 Brass In Storage Atmosphere

The effects of long time storage in the atmosphere containing some organic glue on the surface state and the surface mechanical properties of 0Cr17Ni7 Al steel and HPb63-3 brass, which were used on kinematic pair of a certain type of acceleration switch was analyzed in this paper. The surface topography and component of these two materials was analyzed using optical microscopy, atomic force microscopy(AFM), scanning electron microscopy(SEM), energy disperse spectroscopy(EDS) and X-ray photoelectron spectrum(XPS). The storage effect on the surface topography and chemical composition of these two alloy materials was explored. The surface mechanical properties of the two alloy materials stored under different states were also measured on a nano indentor, in order to clarify the storage effect on the surface mechanical properties.The results of the research indicate that the storage effect on the surface topography and chemical composition of the two alloy materials was similar. The storage leads to the formation of clumps-like depositions with lamellar structure on the surface of the two materials, of which the size and the distribution are not homogeneous and the quantity and the dimension are increased with the storage time. It results in the non- homogeneity of surface topography, the increase of surface roughness Ra, and the elevation of C and O content. The surface of 1:1stored samples has higher value in deposition quantity and size, surface roughness and C and O content, which shows more distinct changes compared to that of the accelerated storage. The storage results in mild oxidation on the surface of0Cr17Ni7 Al steel and increase of ester group on the surface of HPb63-3 brass.The surface nano-hardness and modulus of these two alloys also slightly decrease due to the storage, and the 1:1 stored samples get more distinctive decrease than that of the accelerated test.The storage also leads to the decrease of friction coefficient of the initial stage of wiping, while the final wipe performance is not remarkably changed. There are no distinctive differences between the 1:1 store test and the accelerated test. The 1:1 test shows the similar storage effect on the surface wipe performance of these two alloys.