Thermal shock behavior of Ti3AlC2 from between 200°C and 1300°C
Thermal shock behavior of Ti3AlC2 from between 200°C and 1300°C
复制标题
DOI：
10.1016/j.jeurceramsoc.2004.08.026
复制
发表时间：
2005-09-01
影响因子：
5.7
通讯作者：
Zhou, YC
中科院分区：
文献类型：
--
作者：
Bao, YW;Wang, XH;Zhou, YC
研究了200 ~ 1300 ℃在空气、水和硅油中淬火的Ti 3AlC 2棒材的残余强度和硬度，以探讨Ti 3AlC 2在不同介质中的抗热震性。对于在各种介质中淬火的样品，测得的保留强度显示出不同的趋势。在空气中淬火的试样，残余强度随温度差的增加而有所提高。对于在水中淬火的样品，保留强度表现出复杂的演变，并可分为四个区域，即，(i)无损伤区（20-300 ℃），（ii）强度退化区（300-500 ℃），（iii）稳定强度区（500-1000 ℃），和（iv）强度增强区（1000-1300 ℃）。因此，高于初始强度的60%的第三区域中的最小保留强度提供了Ti 3AlC 2的热冲击强度损失应小于40%的预测。SEM分析表明，在高温下形成了α-Al 2 O 3的氧化皮，并计算了残余应力。在第二温度区的强度退化归因于水渗透引起的晶界弱化，而在第四区的空气淬火样品的强度增强归因于氧化皮的形成和氧化层中的残余压应力。油淬对陶瓷的损伤介于空淬和水淬之间。用有限元法模拟了试样的弯曲破坏过程，结果表明，氧化皮的存在使试样的强度比均匀试样提高了5-10%。(c)2004爱思唯尔有限公司保留所有权利。
The retained strength and hardness of Ti3AlC2 bars quenched from 200 to 1300 degrees C in air, water and silicon oil were investigated to probe the thermal shock resistance of Ti3AlC2 in various media. The measured retained strength displayed different trends for the samples quenched in various media. For the samples quenched in air, the retained strength showed somewhat enhancement with increase of the temperature difference. For the samples quenched in water, the retained strength exhibited a complex evolution and could be divided into four zones, i.e., (i) no damage zone (20-300 degrees C), (ii) strength degradation zone (300-500 degrees C), (iii) stable strength zone (500-1000 degrees C), and (iv) strength enhancement zone (1000-1300 degrees C). Therefore, the minimum retained strength in the third zone, which is higher than 60% of the initial strength, provided a prediction that the strength loss by thermal shock for Ti3AlC2 should be less than 40%. SEM analysis revealed that an oxide scale of alpha-Al2O3 was formed at high temperature for which the residual stress was calculated. The strength degradation in the second temperature zone was imputed to the weakening of grain boundaries caused by water infiltration, whereas the strength enhancements for the air-quenched samples in the fourth zone was attributed to the formation of oxide scale and the residual compressive stresses in the oxide layer. The damage caused by quenching in oil for this ceramic was demonstrated between that of air and water quenching. Finite element method (FEM) was used to simulate the failure in bending, and the results indicated that the strength of the sample with an oxide scale was about 5-10% higher than that of homogeneous sample. (c) 2004 Elsevier Ltd. All rights reserved.