Papers by Keyword: HTP

Abstract: With the development of materials industry, the problem of water pollution is increasingly serious, and therefore it is important to establish an appropriate characterization model of heavy metals in water in China. This paper provides the human toxicity potential factors of several heavy metals, including Hg, Cd, Cr, Pb and As. The result showed that Chinas HTP factors are partial greater than Europe factors, caused by the different industrial situation and the ratio of total human intake to total emissions.

Abstract: The structure and mechanical properties of pipeline steel X80 through HTP rolled into 16mm thick slab were tested. The results show that the yield strength of tested has reached above 600Mpa, and the ratio of tensile strength to yield strength is 0.86, and duetile brittle transition temperature is lower than -60°C , and good strength and toughness are obtained. Low content of P, S, high content of Mn and fine microstructure have good effect on reducing the ductile-brittle transitiop temperature. Two different precipitations are observed in pipeline steel X80, a class of TiN precipitations is mainly and a small number of (Nb, V)(C, N) complex precipitations in the TiN around, and the other for large number of NbC precipitations and a small amount of TiC、VC and simultaneous deposition of the complex formed precipitations. Remarkable strengthening and grain refinement can ne caused by these precipitations.

Abstract: All the SPD techniques introduce reversal straining principally, but effects of the reversal deformation on structure evolution were not studied directly yet. In the present work, an attempt was made to manage structure in pure (99.99%) Al by strain reversal through high pressure torsion (HPT). Total accumulated deformation up to equivalent strain ~8 was used. General trend of the grain refinement is similar for both deformation modes; and it is typical with all other SPD processed FCC metals. At the same time, the difference in microstructure evolution at the vicinity of the specimen axis and with increasing distance in the radial direction introduces microstructural heterogeneities which are specific features of the reversal straining. In the monotonic deformation process the A ({111}<011>) fiber is gradually substituted by the C component ({ 0 0 1}< 1 1 0>) with increasing strain before it is found to weaken. In the reverse straining process the A fiber is found to dominate the deformation texture in the low strain region. In the reverse straining process at high strain level, a {001}<100> component appear.