| 摘要 |
A flat section with density not less than 25% from theoretical value is sintered from the powder of low ductile reactive alloy, welded by diffusion welding with cover foils made from ductile reactive metal that seal hermetically inner and surface pores, and assembled with two heat resistant sheets in the laminated package. Cover foils are made from metal that belongs to the same metal system as said sintered powder. The package is encapsulated in a capsule made from reactive alloy that belongs also to the same metal system as said sintered powder. An anti-adhesive release agent such as Y2O3, A12O3, or CaF2 is deposited on both sides of the laminated package and between cover foils and heat resistant sheets. A portion of metal powder such as Mn, Ti, Nb, Cr, or other metals, having a high affinity to oxygen, inserts into said capsule for absorbtion of oxygen during the heating and forming. After outgassing vacuum heating at 1100-1500 DEG F. and sealing, the capsule with the laminate metal package inside undergoes hot rolling at the temperature range 1800-2450 DEG F. with the reduction for 4-20% of the package thickness. This forming cycle is repeated until the desired thickness and density of said sintered section will be achieved. Thereafter, the formed sintered section is separated from said capsule and heat resistant sheets. The hot isostatic pressing can be used at any step of sintering and forming process for additional compaction and structure improvement of the thin foil or strip produced from low ductile reactive alloy.
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