【摘要】 作者利用x射线能谱仪对YG20C硬质合金冷镦模进行了成分分析。通过x射线衍射,鉴定了合金的粘结相为βCO。它具有面心立方结构,韧性较好。利用扫描电镜和透射电镜对镦模疲劳断口的宏观和微观形貌进行了仔细的观察研究,并借助于背散电子像测量了WC的颗粒度。作者认为:高钴粗晶粒硬质合金的疲劳裂纹是在韧性的钴相中发展,故冷镦模的疲劳断裂具有一般韧性金属高波周疲劳的特征。更多还原

【Abstract】 EDS was used for analysing the composition of a YG20C hard alloy cold upsetting die. The binding phase of the alloy was identified as βCo by X-ray diffraction method. The structure of the phase is F. C. C. and hence it is tough. SEM and TEM were used for observing and researching the macro and micro topography of the fatigue fracture of the die carefully. The particle size of WC was measured by the back scattered electron image. The authors considered that the fatigue crazes of the high cobalt hard alloy developed in the tough phase—Co, hence the fatigue fracture of the die had the characteristic of high frequency fatigue of the common tough metals.更多还原