摘要
采用热压工艺制备了HA/316L粉非对称生物功能梯度材料(FGM)。HA/316L粉非对称生物FGM在宏观上呈现明显的梯度,微观上则表现出成分连续变化,且各成分分布均匀、弥散。在各梯度层内部及界面都没有裂纹及大孔洞出现,界面结合紧密。随着316L粉的含量增加,韧窝的数量逐渐增加,韧窝形貌由浅变深,边缘由尖锐逐渐变得圆滑,表明材料由脆性断裂向韧性断裂转化。纯HA梯度层为典型的脆性断裂,HA80/316L和HA60/316L梯度层表现为典型的晶间断裂,HA40/316L和HA20/316L梯度层断裂性质为晶间断裂中掺杂有韧性断裂,而316L梯度层则表现为典型的韧性断裂。316L粉的加入改变了HA/316L粉生物FGM各梯度层的断裂方式,从而提高了材料的力学性能。从整体上而言,HA/316L粉生物FGM主要增韧机制包括层间裂纹偏转增韧与裂纹偏转增韧。
HA/316L powder asymmetrical biological functionally gradient materials（FGM） were fabricated by hot pressing technique. The results show that obvious gradient changes in macroscopic are shown in the FGM, in which the components change continuously in microcosmic and each component distributes evenly and dispersedly. No flaws or big pores appear in the bulks and interfaces of the gradient layers and the interfaces among all gradient layers unite tightly. With the increase of 316L powder＇s contents, ductile dimples increase and dimple appearance changes from fleet to deep and dimple brim changes from sharp to smooth, which indicates the transformation from brittle fracture to ductile fracture in the composites. Consequently, pure HA gradient layer behaves typical brittle fracture, HA80/316L and HA60/316L gradient layers behave intergranular fracture, HA40/316L and HA20/316L gradient layers exhibit intergranular fracture mingled with ductile fracture, while 316L gradient layer exhibits typical ductile fracture. The addition of 316L powder changes the fracture way of the composites and improves their mechanical properties. There is to exist two toughing mechanisms including interbedded crack deflection and crack deflection in the FGMs.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2008年第12期2129-2133,共5页
Rare Metal Materials and Engineering
基金
国家自然科学基金资助项目(50604017)
中南大学博士后科学基金资助项目
