Effect of Yttrium on High Temperature Oxidation Resistance of a Directionally Solidified Superalloy

The effect of rare earth element yttrium on the high temperature oxidation resistance of a directionally solidified Ni-base superalloy was studied with scanning electron microscopy (SEM), energy dispersive spectrum (EDS) and X-ray diffraction(XRD) techniques. The results show that the oxidation resistance of the alloy is substantially improved by adding proper amount of yttrium.     

稀土Y离子注入对形成不同类型氧化膜合金的高温抗氧化性能的影响

：研究了稀土Ｙ离子注入对ＦｅＣｒ,ＦｅＣｒＡｌ及ＮｉＣｒ合金高温抗氧化性能的影响。结果表明,对于主要形成Ｃｒ２Ｏ３膜的ＦｅＣｒ和ＮｉＣｒ合金,通过离子注入Ｙ可以明显提高其高温抗氧化性能,但对形成Ａｌ２Ｏ３膜的ＦｅＣｒＡｌ合金,离子注入对合金抗氧化性能没有影响,添加稀土Ｙ则使ＦｅＣｒＡｌ合金抗氧化性能大大提高。分析了氧化前、后氧化膜结构变化,认为早期形成的Ｙ２Ｏ３膜对高温氧化时金属离子的扩散有不同的影响     

Influence of cyclic frequency on oxidation behavior of K38 superalloy with yttrium additions at 1 273 K

Cyclic oxidation test is a fundamental method to assess lifetime of materials in high temperature environment.Cycle length or cyclic frequency is one important variable in cyclic oxidation testing.In present work,cyclic oxidation tests were performed on cast K38 alloys with 0 wt.%,0.1 wt.%,and 0.5 wt.% yttrium additions at 1 273 K respectively.Two cyclic frequencies were used to investigate the influence of cycle length (1 h vs.20 h) on the high temperature oxidation behavior of superalloy.The results showe...     

Effect of Yttrium Pre-Implantation on Implantation Behavior of Ti-6Al-4V Alloy in Nitrogen Plasma Immersion Ion Implantation

Ｔｉ 6Ａｌ 4Ｖａｌｌｏｙｈａｓｂｅｅｎｗｉｄｅｌｙｕｓｅｄｉｎｍａｎｙｒｅｓｐｅｃｔｓｓｕｃｈａｓｓｐａｃｅｃｒａｆｔ,ａｉｒｃｒａｆｔａｎｄｂｉｏｍｅｄｉｃａｌａｒｅａｆｏｒｉｔｓｇｏｏｄｐｒｏｐｅｒｔｉｅｓ .Ｈｏｗｅｖ ｅｒ ,ｔｈｅｗｅａｒｒｅｓｉｓｔａｎｃｅｏｆｔｈｉｓａｌｌｏｙｉｓｎｏｔｖｅｒｙｇｏｏｄ[1] .Ｉｔｉｓｗｅｌｌｋｎｏｗｎｔｈａｔｉｏｎｉｍｐｌａｎｔａｔｉｏｎｉｓａｇｏｏｄｍｅｔｈｏｄｉｎｅｎｈａｎｃｅｍｅｎｔｏｆｓｕｒｆａｃｅｐｒｏｐｅｒｔｉｅｓｓｕｃｈａｓｃｏｒｒｏｓｉｏｎ…     

Effect of Cerium on Microstructures and High Temperature Oxidation Resistance of An Nb-Si System In-Situ Composite

Nb-16Si-24Ti-6Cr-6A1-2Hf-xCe （x =0, 0.05, 0.1,02.5, 0.5, 1 （%, atom fraction）） in situ composites were prepared by arc melting The microstmcture and the effect of rare earth element cerium on 1250℃ oxidation resistance of the composites were investigated with scanning electron microscopy （SEM） and X-ray energy disperse spectrum （EDS）, as well as X-ray diffraction （XRD）. The experimental results showed that the high temperature oxidation resistance of the alloy was improved by adding a proper amount of cerium （Ce）. The effect of Ce was considered as the concurrent of the following three factors： first, the oxide of Ce formed in the interface reduced the internal oxidation rate; second, the lath shaped oxide containing Ce increased the cracking resistance and reduced the expansion of the oxide scale; and third, the decrease of the sificide volume fraction on account of Ce addition reduces the power of the sample resisting oxygen penetration.     

Ce对热浸镀铝HP40Nb钢氧化行为及组织的影响研究

通过SEM,EDS和XRD研究了Ce对HP40Nb热浸镀铝层组织结构和高温抗氧化性能的影响.结果表明,热浸镀过程中添加质量分数1％Ce促进了镀层外层中Fe2Al5和Fe4Al3Ce相的生成,抑制了内层Fe2Al5相长大;在1 000 ℃/4 h扩散处理过程中,Ce促进了γ向α相的转变以及α相中Ni3Al相的析出,并在渗层内层中生成富Ce相;800C/360 h氧化后,Ce促使渗层外层生成少量Fe2Al5和Cr3Si相,并使渗层外层组织均匀致密;1000℃/360 h氧化后,Ce促使α相长大导致渗层中生成大量的σ相.800℃氧化实验发现1％Ce使渗层组织致密,提高了渗层高温抗氧化性;1 000℃氧化实验发现1％Ce促进了渗层中σ相的生成,阻碍了Al原子的内扩散,保证了氧化过程中渗层表面生成α - Al2O3所需铝含量.     

Influence of yttrium addition on high temperature oxidation resistance of single crystal superalloy

Two experimental single crystal superalloys Y-free alloy and Y-containing alloy were cast in the directionally solidified furnace, while other alloying element contents were basically kept unchanged. T...     

Thermal Oxidation Resistance of Rare Earth-Containing Composite Elastomer

Ｏｌｅｆｉｎｅｒｕｂｂｅｒｃｏｎｔａｉｎｉｎｇｕｎｓａｔｕｒａｔｅｄｃａｒ ｂｏｃｈａｉｎｌｉｋｅＮＲｅｔｃ .ｉｓｍｏｒｅｅａｓｉｌｙｏｘｉｄａｔｉｖｅ ａｇｅｄｔｈａｎｒｕｂｂｅｒｃｏｎｔａｉｎｉｎｇｓａｔｕｒａｔｅｄｃａｒ ｂｏｃｈａｉｎｉｓ .Ｕｓｕａｌｌｙ ,ａｎｔｉｏｘｉｄａｎｔｓａｒｅｄｏｐｅｄｔｏｐｒｅｖｅｎｔｐｏｌｙｍｅｒｍａｔｅｒｉａｌｆｒｏｍｂｅｉｎｇｏｘｉｄｉｚｅｄ .Ｂｕｔｉｔｉｓａｌｓｏｒｅｐｏｒｔｅｄｔｈａｔｒａｒｅｅａｒｔｈｃｏｍ ｐｏｕｎｄｓ[1,2 ] ,ｍｅｔａｌｏｘｉｄｅｓａ…     

稀土氧化物对焊缝金属抗高温氧化腐蚀性能的影响

本文通过在焊条药皮中分别添加微量稀土氧化物Ｌａ２Ｏ３及ＣｅＯ２,研究其对焊条熔敷金属在空气中和含硫气氛中抗高温氧化及腐蚀性能的影响。结果表明：微量稀土氧化物在焊条药皮中的加入,对其熔敷金属抗高温氧化性能有所提高,对在含硫气氛中的抗高温腐蚀性能有显著提高,添加Ｌａ２Ｏ３的焊条熔敷金属比添加ＣｅＯ２的焊条具有更好的抗高温硫腐蚀性能。     

钛合金表面抗氧化改性技术

本文介绍了为提高钛合金表面抗氧化性能将等离子喷涂技术、离子注入法应用于钛合金表面改性技术取得的进展,重点介绍了每种工艺方法的基本情况、特点及应用。