抗高溫剝落性能的影響
( 1. 西安理工大學(xué) 材料科學(xué)與工程學(xué)院， 西安 710048;
2. 洛陽(yáng)工業(yè)高等專科學(xué)校 材料系， 洛陽(yáng) 471003;
3. 河南科技大學(xué) 材料科學(xué)與工程學(xué)院， 洛陽(yáng) 471003)
摘 要: 通過(guò)高溫氧化實(shí)驗(yàn)以及測(cè)量空洞平均直徑和形核數(shù)量隨氧化時(shí)間的變化， 研究稀土對(duì)滲鋁層抗高溫剝落性能和滲鋁層/基體界面空洞生長(zhǎng)的影響， 并與滲純鋁試樣進(jìn)行了比較。 結(jié)果表明： 滲鋁層/基體界面空洞的生長(zhǎng)可劃分為快速生長(zhǎng)和穩(wěn)定生長(zhǎng)兩個(gè)階段；但當(dāng)滲稀土鋁后， 空洞生長(zhǎng)速度比滲純鋁試樣降低約1/3； 稀土可抑制界面空洞的形核和生長(zhǎng)， 阻止空洞聚集成波浪線狀空洞帶和線狀裂紋，提高滲鋁鋼的抗高溫剝落性能； 熱浸鍍稀土鋁后， 試樣表面自由鋁層減薄， 從而降低了高溫下滲鋁層/基體界面鋁的濃度梯度，這是稀土抑制空洞形核和生長(zhǎng)的主要原因。
關(guān)鍵字: 稀土； 滲鋁鋼； 空洞； 抗氧化性能； 剝落性能
WEN Jiu-ba3， FAN Zhi-kang1
（ 1. School of Materials Science and Engineering,
Xi'an University of Technology, Xi'an 710048， China;
2. Department of Materials Engineering,
Luoyang College of Technology, Luoyang 471003, China;
3. School of Materials Science and Engineering,
Henan University of Science and Technology, Luoyang 471003, China）
Abstract: The effects of rare earth (RE) elements on the void formation in aluminized coating and the spalling resistance of aluminized steel were investigated through cyclic oxidation test and measurement of the variations of the average size and the number of the voids with oxidation time, and compared with those of plain aluminized steel without RE. The results show that the growth of the voids can be divided into two stages of fast growth and stable growth, and the growth speed of the void of the RE-added aluminized coating decreases by about 1/3, in comparison with that of the plain aluminized coating. RE addition can restrain the formation and aggregation of voids and subsequently improve the oxidation and spalling resistance. The main reason why RE restrains the formation and the growth of voids is the concentration gradient of aluminum decreases at high temperature due to the decrement of the thickness of pure aluminum coating after hot dip RE-aluminizing.
Key words: rare earth; aluminized steel; void; oxidation resistance; spalling resistance
