Diamond Products With The Preparation And Performance Of The Pre-alloy Powder

Atomization is used to prepare prealloyed powder. Although the prealloyed powder that prepared by atomization possess lower sinter temperature and higher alloying extent, the atomization has some disadvantage, such as better equipment, difficult to adjust matrix composition, higer cost, and so on. Hence, it is important that investigate new preparing method for prealloyed powder.Compare to atomization, the co-precipitation and reduce method possess merits as follows: do not use purity metal which is costly highly as material, but directly begin from inorganic salts, which avoids smelt process for high purity metal; the alloying could process at relative low temperature because the mixing of several metal elements is very uniformity at co-precipitation process, that avoid high temperature melting and long time homogenization heat treatment for atomization; could exactly control content of several composition, make different composition reach molecule/atom level homogenization, the powders have good sinter ability and equipment for preparation is simple.Prealloyed powder for diamond products was prepared by co-precipitation and reduce method in this paper. The main content and conclusion are as follows:(1). The influence of co-precipitation and reduce technics on prealloy powders were investigated. For Fe²⁺, Co²⁺ and Cu²⁺ metal irons, the precipitator adopt oxalic acid .The FeCoCu prealloyed powder has state composition according to formula and good crystal is obtained under condition that are proposed: co-precipitation temperature is 50-70°C, both the metal-salt solution A and complex precipitator B concentration are 0.5-0.8 mol·L^-1,co-precipitation mode is quick parallel-flow, reduce temperature is 510-550°C and reduce time is 30-50min.(2). The performance of prealloyed poweder for diamond products matrix was investigated. The results show that the hardness and blank matrix bending strength of matrix prepared by co-precipitation and reduction are relatively lower than matrix that prepared by atomization, but hold coefficient and blending strength that contain diamond of matrix that prepared by co-precipitation and reduction are higher than matrix of atomization. Appearance of fracture of samples prepared by co-precipitation and reduction are similar to the samples of atomization, both present radiate stripe and are brittleness rupture.(3). The performance of prealloyed poweder for transition layer of laser welding was investigated. The results show that the welding performance of samples fabricated by higher temperature is better than that of lower temperature, and the welding strength reaches 51.6 N·m at 850°C, but the welding strength of samples fabricated by lower temperature also could reach produce requirement. And the influence of Cu content on the performance of FeCo matrix prealloyed powder for transition layer was also investigated. The results show that both the welding performance of FeCo2Cu and FeCo4Cu prealloyed powder are better than FeCo prealloyed powder, and FeCo2Cu prealloyed powder possess high welding strength at all sinter temperature and it is the best welding performance among three prealloyed powder.