刘建涛
,
林鑫
,
吕晓卫
,
陈静
,
黄卫东
金属学报
采用激光立体成形技术制备了从Ti到Ti2AlNb成分连续渐变、外形规则、高度为17 mm的梯度材料. 分析了梯度材料的组织及相结构演变规律和硬度变化规律. 随着Al和Nb成分的提高,Ti-Ti2AlNb功能梯度材料的相呈现α' → α+β → α+α' → α' → α+β → α+β/B2+α2 → β/B2+α2 → β/B2 →B2+ α2+O→ B2的演变过程, 实现了由$α$型钛合金经过α+β型及β型钛合金向Ti2AlNb基合金的转变. 硬度值HV从底部纯Ti的170连续
渐变到顶端Ti2AlNb的470. 基于钛合金富Ti区非平衡相图, 并结合Al和Nb元素在钛合金中对α, β和α2稳定性的影响分析, 对梯度材料在激光立体成形过程中的相演化过
程进行了解释.
关键词:
激光立体成形
,
Titanium
,
Ti2AlNb
,
Functionally graded materials
,
Phase transformations
Yuewu PAN
,
Jie YU
,
Zhan HU
,
Hongdong LI
,
Qiliang CUI
,
Guangtian ZOU
,
null
,
null
,
null
材料科学技术（英文）
ZnS nano-particles with average sizes of 10 nm and 5 nm were fabricated by sol-gel method, and their pressure-induced phase transformations were in-situ examined in a diamond anvil cell by energy dispersive X-ray diffraction (EDXD) from ambient pressure to 35.0 GPa. From the obtained interplanar spacing data, the volume compression ratios were derived at different pressures, and then the bulk modulus and its pressure derivative were obtained by fitting to the Murnaghan equation. It is found that both ZnS nano-particles initially in the zinc-blende phase transformed to cubic NaCl structure in the presence of pressure and the transition was reversible when the pressure was released. Moreover, it is suggested that a smaller particle size will induce a larger transition pressure.
关键词:
Nano-particles
,
null
,
null
,
null
