Kinetics of layer growth and multiphase diffusion in ion- nitrided titanium
Kinetics of layer growth and multiphase diffusion in ion- nitrided titanium
复制标题
离子氮化钛中层生长和多相扩散的动力学
DOI：
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发表时间：
1989
期刊：
影响因子：
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通讯作者：
O. Inal
中科院分区：
文献类型：
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作者：
E. Metin;O. Inal
纯钛试样在800 ℃ ~ 1080 ℃的温度范围内，在不同的氮分压下，在氮等离子体中进行离子氮化。在离子渗氮过程中，形成了与平衡相图一致的氮化钛TiN和TiIn 2N以及氮固溶体层（α和B）。这些层的生长动力学作为一个函数的温度和离子渗氮参数进行了研究。采用多相扩散的解析扩散模型，计算了氮在Ti-TiN系各相的扩散系数。使用层生长数据，发现TiN（δ）、Ti 2N（ε）和α钛中氮扩散的温度依赖性遵循以下关系：Dinδ=4.4±1.62 × 10su-5 exp-36，500 ±1400/RT Dinε=2.7±1.05 ×10su-3 exp-35，760 ±2500/RT Dinα=0.96±0.08 × exp-51，280-505/RT在900 ℃离子氮化的试样中测量氮的浓度分布。在高氮浓度下，该配置文件与预测值吻合良好。然而，在低氮浓度下，观察到的偏差，假设是由于钛中的氮扩散的浓度依赖性。
Pure titanium specimens were ion nitrided in a nitrogen plasma in the temperature range of 800 ‡C to 1080 ‡C at various nitrogen partial pressures. During ion nitriding, titanium nitrides TiN and Tiin2N and nitrogen solid solution layers (α and Β) were formed consistent with the equilibrium phase diagram. The kinetics of growth of these layers were studied as a function temperature and ion-nitriding parameters. An analytical diffusion model for multiphase diffusion was used to calculate the diffusion coefficients of nitrogen in the phases of the Ti-TiN system from layer growth experiments. Using the layer growth data, the temperature dependence of nitrogen diffusion in TiN (δ), Ti2N (ε), and α titanium was found to obey the following relations: Dinδ=4.4±1.62 × 10su-5 exp-36,500±1400/RT Dinε=2.7±1.05 ×10su-3 exp-35,760±2500/RT Dinα=0.96±0.08 × exp-51,280-505/RTConcentration profiles of nitrogen were measured in specimens ion nitrided at 900 ‡C. The profiles were in good agreement with the predicted ones at high nitrogen concentrations. How-ever, at low nitrogen concentrations, a deviation was observed, assumed to be due to a con-centration dependence of nitrogen diffusion in a titanium.