热处理工艺对氧化物弥散强化Fe-Cr合金微观结构和致密化的影响
Effect of heat treatment on microstructure and densification of oxide dispersion strengthened Fe-Cr alloy
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摘要: 将预合金粉雾化粉与Ti粉、纳米Y2O3粉混合后进行机械合金化，所得粉末用热等静压进行固结，采用不同的热处理参数对所得样品进行热处理。利用扫描电镜及透射电镜（TEM）等检测工具进行检测。结果表明，机械合金化中导致的孔洞会在热等静压后保留在试样基体中，随正火温度的提高，孔洞的形貌由不规则大孔洞变为细小均匀分散的小孔;在1 100 ℃下保温5 h后，孔洞粗化。TEM显示，随正火温度的提高，晶粒发生长大而粗化，并伴随着显微硬度的下降，当在1 050 ℃后继续增加温度，则硬度变化不明显。Abstract: Fe-Cr pre-alloyed powders, pure Ti powders and nano Y2O3 powders were processed by mechanical alloying (MA), and then the as-milled powders were sintered by hot isostatic pressing (HIP). Different heat treatment processes were conducted on the consolidated samples. The microstructure evolution was investigated by XRD, SEM and TEM. Voids resulted from MA are remained in matrix during HIP, but the initial morphology is changed, and the regular small voids instead of irregular large voids are distributed homogeneously. Voids are linked up each other and developed into larger voids after annealing at 1 100 ℃ for 5 h. TEM images indicate that grain coarsening is occurred with the increasing normalizing temperature, while the microhardness is decreased sharply until 1 050 ℃.
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Keywords:
- mechanical alloying ,
- ferrite ,
- oxide dispersion strengthening ,
- hot isostatic pressing ,
- void
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[1] UKAI S, NISHIDA T, OKUDAT, et al. R&D of oxide dispersion strengthened ferritic martensitic steels for FBR[J]. Journal of Nuclear Materials, 1998, 258-263: 1 745-1 749. [2] CHO H S, KIMURA A, UKAI S, et al. Corrosion properties of oxide dispersion strengthened steels in super-critical water environment[J]. Journal of Nuclear Materials, 2004, 329-333: 387-391. [3] CHO H S, KIMURA A. Corrosion properities of oxide dispersion strengthened ferritic steels in super-critical pressurized water[J]. Journal of Nuclear Materials, 2007, 367-370: 1 180-1 184. [4] SAKASEGAWA H, OHTSUKA S, UKAI S, et al. Microstructural evolution during creep of 9Cr-ODS steels[J]. Fusion Engineering and Design, 2006, 81(8-14): 1 013-1 018. [5] 冯涤，李力．IN100高温合金粉末在加热过程中的相转变和原始颗粒边界问题[J] ．钢铁研究学报，1983，３(4)：565-573.
FENG Di, LI Li. Phase transformation during heating and ppb problems in pm superalloy IN100[J] ． Journal of Iron and Steel Research, 1983, 3(4): 565-573(in Chinese).[6] CHEN Y L, JONES A R, MILLER U. Origin of porosity in oxide-dispersion-strengthened alloys produced by mechanical alloying[J]. Metallurgical and Materials Transactions A, 2002(33): 2 713-2 718.
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