• Kaiser, Andreas
• Ernst, Peter

Abstract

Production of a granulate-containing hard material (H) for thermal sputtering comprises - (a) mixing the hard material (H) with a binder metal (M); - (b) adding a sintering aid (A); - (c) forming a slip; - (d) spray drying; - (e) calcining; and - (f) mechanically separating the agglomerated particles to give the product (P). - Production of a granulate-containing hard material (H) for thermal sputtering involves the following steps (a) - (f) with steps (a) - (c) optionally combined into 1 or 2 steps : - (a) mixing hard material particles (1, H) with a binder metal (M) powder which forms a sintered matrix (2) by calcination; - (b) adding a sintering aid (A); - (c) suspending the solids with a liquid (L) to form a slip and adding a dispersant (D) as well as a binder (B) to reduce the amount of L in the slip to a minimum; - (d) spray drying the slip to separate L from the solids H and M which are agglomerated to give particles (3) forming, on account of the binder, a stable spray granulate (G); - (e) calcining G at a temperature at which the binder metal forms a matrix (2) between the hard material particles within the agglomerated particles, the density of the agglomerated particles being at least 10% higher than that of the uncalcined spray granulate; and - (f) producing a powdered product (P) by separating the agglomerated particles which are bonded to each other by the calcination, this separation being effected by mechanical means (especially breaking) and the resulting material being classified (especially by sieving) to yield a powder of the required particle size distribution.

Topics

• density
• forming
• drying
• sintering