EFFECT OF TRANSITION-METAL ADDITION ON LIQUID-PHASE SINTERING OF W-CU

Cobalt, iron, and nickel were added to copper in order to accelerate t he liquid phase sintering process of W-Cu composite. The sintering beh aviour of tungsten with additions of these elements varied widely depe nding on the addition element even though the rate of densification co uld be significantly enhanced by suitable additions of these elements. Additions in excess of the amount necessary to form a continuous laye r lead to successively decreasing sintering rates in the case of cobal t, while no decrease could be observed with increase in the quantity o f added iron, and the sintering rate increased continuously with incre asing nickel additions. The difference in the wettability of the tungs ten surface by the liquid copper was attributed to the effects of addi tives on liquid phase sintering of W-Cu compacts.