ISSN:
1573-9066
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Conclusions A study was made of the densification kinetics in the hot pressing of chromium carbide and its alloys under pressures of 10.8–21.6 MPa at temperatures of 1350–1500°C for Cr3C2 and 900–1200°C for KKhN-15 and KKhNF-15 alloys in the isothermal holding time range from 300 to 1500 sec. It was found that increasing the duration of isothermal holding at all the temperatures and pressures investigated increased the relative densities of the materials from 0.65–0.7 at the lowest pressures and temperatures to 0.98–0.99 at the maximum values of these parameters. It is shown that the densification of chromium carbide and its alloys with nickel and nickel-phosphorus binders in hot pressing is described by a generalized equation of volume viscous flow of a porous solid; for Cr3C2 it is determined by nonlinear creep and for KKhN-15 and KKhNF-15 alloys by a linear flow of the solid particles of their carbide components in their liquid cementing phases. The energies of activation for creep are: 3.8 eV for chromium carbide, 1.8 eV for KKhN-15, and 1.5 eV for KKhNF-15.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00792517
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