Interaction of Components of Co-Sn and Co-Sn-Cu Powder Materials in Liquid Phase Sintering

Abstract

The interaction of components and structure formation were studied in liquid phase sintering of Co-Sn and Co-Sn-Cu powder materials. The powders of commercially pure metals were mixed with an organic binder and applied on the steel substrate. Sintering was performed under vacuum at temperatures of 820 and 1100 °C. The structure of sintered alloys was investigated by X-ray diffractometry and electron probe microanalysis, and microhardness (HV0.01) of the structural components was measured. It has been found that the nature of interaction of the liquid tin with the solid phase at the initial stage of sintering affects the formation of structure and porosity of Co-Sn and Co-Sn-Cu alloys considerably. In Co-Sn alloys, diffusion of tin into cobalt particles leads to the formation of intermetallic compounds, which hinders spreading of the liquid phase. This results in a porous defect structure formed in Co-Sn alloys. In Co-Sn-Cu alloys, at the initial stage of sintering the liquid phase enriched with copper is formed that wets the cobalt particles and contributes to their regrouping. As a result of this, materials with minor porosity are formed.

Corrosion and methods of material protection

“…Коррозия оказывает негативное воздействие на металлы, бетон, пластик и другие материалы, что, в свою очередь, может привести к экономическим потерям и опасным ситуациям в инфраструктуре и промышленности. Для того чтобы эффективно бороться с этой проблемой, важно понимать ее природу и разрабатывать методы защиты материалов [1].…”

Structure Formation of Diamond-Containing Coatings during Sintering of Specially-Shaped Grinding Wheels

“…To help counter this, special compositions of Sn-Cu-Co powder materials have been developed. Their sintering is accompanied by a large quantity of the liquid phase forming [10][11][12]. The liquid phase facilitates regrouping of the solid phase particles, which helps alleviate shrinkage stresses.…”