论文部分内容阅读
通过化学成分分析、金相显微镜和扫描电镜等观察,对M12粉末高速钢丝锥进行了剖析。分析结果表明,丝锥中的碳和合金含量很高,其中Co和V含量分别高于10%(质量分数,下同)和4%,合金总含量超过了40%,钢质纯净,夹杂物很少。丝锥硬度高达70 HRC左右,表面经过Ti(C、N)涂层,厚度约2μm,与基体结合紧密,能够切削硬度高于50 HRC的超高强度钢。丝锥中的碳化物类型为M6C和MC,单颗碳化物直径≤3μm,分布比较均匀;但碳化物粘连现象较严重,并有部分沿奥氏体晶界延伸生长等过热缺陷,使丝锥脆性增大。这是由于钢中合金含量很高,碳化物数量多且细小,使其容易合并、长大、粘连。因此在粉末高速钢的生产过程中,应根据这些特点合理制定生产工艺并严格执行,避免产生过热,使粉末高速钢的高性能特点得到充分发挥。
Through the analysis of chemical composition, metallographic microscope and scanning electron microscope, the M12 powder high-speed steel tap was analyzed. The results show that the content of carbon and alloy in the tap is very high. The contents of Co and V are higher than 10% (mass fraction) and 4% respectively. The total content of the alloy is more than 40% less. Tap hardness of up to 70 HRC or so, the surface after Ti (C, N) coating, a thickness of about 2μm, combined with the substrate close, capable of cutting high hardness steel above 50 HRC. The types of carbides in tap are M6C and MC, the diameter of single carbide is less than or equal to 3μm, and the distribution is relatively uniform. However, the phenomenon of carbide adhesion is serious and some overheat defects such as the growth and growth along the austenite grain boundaries make the brittleness increase Big. This is due to the high alloy content of steel, carbides and small number, making it easy to merge, grow up, adhesion. Therefore, in the production process of powder high-speed steel, the production process should be rationally formulated according to these characteristics and strictly implemented to avoid overheating, thus giving full play to the high-performance characteristics of the powder high-speed steel.