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 1. The optimum compaction pressure may be taken to be 4 tons/cm2, since higher pressures give rise to cracking and layering. 2. The highest density is exhibited by specimens pressed from powders prepared by the reduction of an oxide mixture in hydrogen at a temperature of 900°C. The reason for this is that the particles of such powder consist essentially of a solid solution, whose ductility is higher than that of a chemical compound. 3. After sintering, specimens prepared from powders reduced under different conditions exhibit substantial differences in density and volume shrinkage. The highest density is possessed by specimens pressed from powders reduced from a mixture of oxides at 750°C (600°C for NIMO-20 alloy). This may be ascribed to the high activity of particles of such powders (crystal lattice defectiveness, small size, and existence of several phases). With rise in temperature, the activity diminishes, as a result of which sintered specimens of lower density are obtained.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00836961
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