烧结钼钢的动力学性能

Dynamic properties of sintered molybdenum steels

许多粉末冶金应用 ,要求烧结零件能耐高的静力学和动力学工作应力。提高烧结密度是提高动力学性能 ,获得适当显微组织的关键参数之一。在市场上的低合金钢粉中 ,低钼合金钢粉令人感兴趣 ,因为这种合金元素仅对粉末压制性有轻微影响 ,却很有效地提高淬透性和力学性能。此外 ,像Ni和Cu关键性元素混合到基础钢粉中或在退火处理过程中扩散粘结到钢颗粒上 ,也会通过改善显微组织使力学性能提高。本文研究了含有不同量的预合金的低Mo合金钢粉的抗拉和动力学性能。也讨论了将Ni和Cu预混合或扩散粘结到这些钼钢中的作用 ,特别是对轴向疲劳性能和强度的影响。还与其它类型疲劳试样和

A large number of P/M applications require sintered components capable of withstanding high operational static and dynamic stresses Raising sintered density is one of the key parameters to enhance dynamic properties together with appropriate microstructure Amongst the low alloyed steel opwders available on the market,low alloy Mo powders present interesting attributes because this alloying element only sllghtly affects powder compressibility and is very efficient to increase hardenability and hence mechanical properties Fatmurthermore,the addition of key elemental additives such as Ni and Cu admixed to the base steel powders or diffusion bonded to the steel particles during the annealing treament also contributes to improve the mechanical properties though modification of the microstructure This paper reports the results of a study to characterize the tensile and dynamic properties of low alloy steel powders containing various levels of pre alloyed molybdenum the effect of either admixing or diffusion bounding Ni and Cu to these Mo steels is also discussed particularly withrespect to axial fatigue properties and strength Comparison with results obtained with other types of fatigue specimens and/or testing methods is also presented