稀土提高40Cr钢氮化层抗冲蚀磨损性能的研究

本文研究了在气体氮化渗剂中加入微量稀土元素对40Cr钢氮化层组织、韧性及抗冲蚀磨损性能的影响。试验结果表明稀土在氮化时被渗入到钢的表层起微合金化作用,改善了渗层组织。稀土氮化层的韧性和抗冲蚀磨损性能,较普通氮化层有明显提高。扫描电子显微镜对冲蚀磨损试样表面形貌观察发现,氮化层的磨损特征为塑性变形形成的犁沟剥落,并伴随着萌生横向裂纹,有大块磨屑剥落;而稀土氮化层则为塑性变形形成的犁沟剥落。     

稀土对ZG60CrMnSiMo钢冲击疲劳抗力的影响

加入适量稀土能提高ＺＧ６０ＣｒＭｎＳｉＭｏ 钢的冲击疲劳抗力,过量反而导致性能恶化。     

Preparation and Corrosion Resistance of Rare Earth Conversion Coatings on AZ91 Magnesium Alloy

Magnesiumalloysarewidelyusedinweaponin dustry,spacenavigationandhavegoodpotentialof applicationanddevelopmentindailycommunication facilitiesduetotheirpropertiesoflightweightandhighstrength[1].Appliedasstructuralmaterials,mag nesiumalloysmayeasilycrackduet…     

Effect of Rare Earth Elements on Quenching Crack Resistance of Steel 9Cr2Mo

Ｒｏｌｌｅｒｆｏｒｃｏｌｄｒｏｌｌｉｎｇｉｓａｋｅｙｆｏｒｇｉｎｇｐａｒｔ,ｗｈｉｃｈｅｘｐｅｒｉｅｎｃｅｓｃｏｎｔａｃｔｓｔｒｅｓｓ ,ａｌｔｅｒ ｎａｔｉｎｇｓｔｒｅｓｓａｎｄｆｒｉｃｔｉｏｎａｌｓｔｒｅｓｓｄｕｒｉｎｇｒｏｌｌｉｎｇ .Ｔｈｅｒｅｆｏｒｅ ,ｈｉｇｈｅｒｓｔｒｅｎｇｔｈ ,ｓｕｒｆａｃｅｈａｒｄｎｅｓｓ,ｗｅａｒｒｅｓｉｓｔａｎｃｅａｎｄｅｎｏｕｇｈｔｏｕｇｈ ｎｅｓｓｓｈｏｕｌｄｂｅｃｏｎｓｉｄｅｒｅｄｆｏｒｍａｎｕｆａｃｔｕｒｉｎｇｔｈｉｓｃｏｌｄｒｏｌｌｅｒ[1] .Ｓｉｎｃｅｔｈｅ…     

稀土改善430铁素体不锈钢冲击韧性的作用机理

 采用金相、扫描电镜和能谱等分析手段,研究了微量稀土对430铁素体不锈钢在室温和低温下的横向冲击性能的影响。研究结果表明,稀土夹杂物减缓了裂纹的扩展。加稀土的试样断口为韧性撕裂,不加稀土的试样断口为解理断裂。加微量稀土的试样横向冲击性能比不加稀土的试样大幅度提高,最高提高了5倍。     

稀土元素的特殊性质及其应用

本文从稀土元素微观结构角度，揭示了稀土元素的某些特殊性质，并指出这种特性与应用机理有必然的联系。从而启迪稀土使用者，掌握和了解稀土的基本特性，才能自由地驾驭稀土的应用。     

稀土元素对奥氏体不锈钢焊条熔敷金属组织和性能的影响

在奥氏体不锈钢焊条中，通过在焊条药皮中加入稀土元素。探讨了其对焊条熔敷金属组织和性能的影响。对加稀土前后两种焊条进行了熔敷金属常规拉伸和冲击试验。宏观金相组织分析和冲击断口扫描电镜分析。并对熔敷金属薄片进行了透射电镜分析。结果表明：在奥氏体不锈钢焊条药皮中加入稀土元素。可以细化结晶组织，改变晶界上碳化物的析出形态和分布，并使碳化物的析出数量和颗粒尺寸明显减小，从而净化了奥氏体晶界，提高了其焊条熔敷金属的机械性能。     

Influence of Rare Earth Elements on Microstructure and Mechanical Properties of Cast High-Speed Steel Rolls

The influence of rare earth （RE） elements on the solidification process and eutectic transformation and mechanical properties of the high-V type cast, high-speed steel roll was studied. Test materials with different RE additions were prepared on a horizontal centrifugal casting machine. The solidification process, eutectic structure transformation, carbide morphology, and the elements present, were all investigated by means of differential scanning calorimetry （DSC） and scanning electron microscopy energy dispersive spectrometry （SEM-EDS）. The energy produced by crack initiation and crack extension was analyzed using a digital impact test machine. It was found that rare earth elements increased the tensile strength of the steel by inducing crystallization of earlier eutectic γ-Fe during the solidification process, which in turn increased the solidification temperature and thinned the dendritic grains. Rare earth elements with large atomic radius changed the lattice parameters of the MC carbide by forming rare earth carbides. This had the effect of dispersing longpole M C carbides to provide carbide grains, thereby, reducing the formation of the gross carbide and making more V available, to increase the secondary hardening process and improve the hardness level. The presence of rare earth elements in the steel raised the impact toughness by changing the mechanism of MC carbide formation, thereby increasing the crack initiation energy.     

Effect of Rare Earths on Composition and Activities of Rare Earth Elements Binding Glycoprotein in Tea

Ｔｅａｐｏｌｙｓａｃｃｈｒｉｄｅｃｏｍｐｌｅｘ ,ｏｎｅｏｆｔｈｅｂａｓｉｃｍａｃｒｏｍｏｌｅｃｕｌｅｓｉｎｔｅａ ,ｈａｓｍａｎｙｐｈａｒ ｍａｃｅｕｔｉｃａｌｅｆｆｅｃｔｓａｎｄｉｓｅａｓｙｔｏｄｉｓｓｏｌｖｅｉｎｔｅａｉｎｆｕｓｉｏｎ[1] .Ｚｈｏｎｇｅｔａｌ .[2 ] ｄｉｓｃｏｖｅｒｅｄｔｈａｔｔｈｅｒｅｉｓａＲＥｂｉｎｄｉｎｇｐｏｌｙｓａｃｃｈａｒｉｄｅｉｎｌｅａｖｅｓｏｆｔｅａｐｌａｎｔ (ＣａｍｅｌｌｉａＳｉｎｅｎｓｉｓＬＯ .Ｋｕｎｔｚｅ) .Ｉｎｔｈｉｓｐａｐｅｒ ,ｔｈｅｓｔｕｄｙｏｎｔｈｅｃｏ…     

稀土对B级船板钢冲击韧性的影响

利用扫描电镜(SEM)和能谱仪(EDS),研究了不同稀土含量对B级船板钢热轧板断口形貌及对钢中夹杂物形成的影响。研究发现,在B级船板钢中加入稀土后,稀土元素La、Ce能够与钢中的As相互作用形成复合相;稀土在钢中起到变质夹杂物的作用,从而提高了钢的低温冲击韧性;在本实验中,稀土的最佳含量为0.019%。     

Electronic Theoretical Study of the Interaction between Rare Earth Elements and Impurities at Grain Boundaries in Steel

Rareearths(RE)aresurfaceactiveelements ,theirapplicationsinmetalmaterialscanbesum marizedaspurification ,modificationandall oying[1～ 3 ] .Itisaveryattractivesubjectthattheinter actionofREelementswithlowmeltingpointimpuri tiesintheregionofGBs ,suchasP ,S ,As ,Sbandsoon .ResultsofexperimentsshowthatsegregationinGBsofasmallamountofREinsteelrestrainsharmfulimpuritiessuchasP ,S ,As ,Pb ,Sb ,tosegregateto wardsGBs ,soREelementscancleanseandenhanceGBs ,therebyimprovethehightemperatureducti…     

稀土元素对Fe-Cr-Al系合金抗氧化性的影响

分析了Cr_2O_3膜和Al_O_3膜性质及生长机制,基于国内外学者已提出的机理,讨论了稀土对Fe-Cr-Al系合金氧化膜的生长机制、膜形貌及膜的粘附性的影响。     

Effect of Rare Earth Elements on Thermal Fatigue Property of Low Chromium Semi-Steel

The effect of rare earth elements on eutectic carbide‘s morphology of low chromium semi-steel in as-cast state and after heat treatment was investigated, and accordingly, the thermal fatigue property of this material was studied. The results show that RE can improve the eutectic carbide‘s morphology, inhibit the formation and propagation of thermal fatigue cracks, therefore, promote the thermal fatigue property, which is more noticeable in case of the RE modification in combination with heat treatment. The optimal thermal fatigue property can be obtained when treated with 0.2% RE modification as well as normalization at 950℃ for 3h.     

Effect of Rare Earth on Thermal Shock Resistance of Steel 9Cr2Mo

Ｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓｈａｖｅｂｅｅｎａｄｄｅｄｉｎｔｏｈｏｔｒｏｌｌｅｒｓｔｅｅｌ.ＲＥｅｌｅｍｅｎｔｓｃａｎｉｍｐｒｏｖｅｔｈｅｒ ｍａｌｆａｔｉｇｕｅ[1] ,ｌｏｗｆｒｅｑｕｅｎｃｙｆａｔｉｇｕｅ[2 ] ,ｐｌａｓ ｔｉｃｉｔｙａｎｄｔｏｕｇｈｎｅｓｓ[3] ,ｒｅｆｉｎｅａｕｓｔｅｎｉｔｉｃｇｒａｉｎｓｉｚｅ[4] ａｎｄｍｏｄｉｆｙｉｎｃｌｕｓｉｏｎｓ[5 ] ｏｆｈｏｔｒｏｌｌｅｒｓｔｅｅｌ 6 0ＣｒＭｎＭｏ .Ｓｔｅｅｌ 9Ｃｒ2Ｍｏｉｓａｔｒａｄｉｔｉｏｎａｌｃｏｌｄｒｏｌｌｅｒｓｔｅｅｌ.Ｗｈｅｎ…     

钢纤维表面渗稀土对摩阻材料耐腐蚀性能和冲击强度的影响

研制了新型的稀土摩阻材料。摩阻材料刹车片中 ,钢纤维通过气 -固表面扩渗稀土处理后 ,表面耐腐蚀性能明显改善 ,抗冲击强度显著提高 ,并且综合性能有所改善。比较了经过渗稀土处理钢纤维与未经渗稀土处理钢纤维制备的摩阻材料刹车片耐腐蚀性能和抗冲击性能 ,初步分析探讨了可能的机理     

Biosorption of Rare Earth Elements

Abstract

By using X-ray microanalysis, the mechanism of sorption of rare earth elements (REE) and their localization in cells of Candida utilis were found to depend on the metal ion speciation in solution, the permeability of the cytoplasmic membrane (CPM), and elemental composition of cells. Sorption capacity of the yeast cells increased with the increase in the pH of solution, which is connected with the extent of metal hydrolysis. Cells with native permeability of CPM did not sorb either scandium at pH values below 4.5 or lanthanum and samarium at pH values below 5.0. Such cells accumulate rare earth elements on surface structures. Only the cells with impaired CPM could sorb REE from the acid solutions. In this case, REE were accumulated inside the cells due to the interaction with phosphorus-containing compounds; the amount of sorbed REE depended on the content of phosphorus in the yeast cells. The yeast cells were shown to have extremely high affinity to scandium which thus can be selectively sorbed from solutions containing other REE, iron, and aluminum.     

残余元素锡、锑对34CrNi3Mo钢冲击韧性的影响及稀土镧的改善作用

利用JB-30B型冲击试验机研究了不同含量的残余元素锡、锑及稀土镧对低氧、低硫的34CrNi3Mo钢冲击韧性的影响;采用SEM及EDS手段研究了稀土镧对不同锡、锑含量钢的断裂方式的影响以及在钢中形成化合物的情形.结果表明:稀土金属可以明显改善低氧、低硫钢中残余元素对钢性能的危害;镧可与钢中的残余元素作用形成复合相且分布均匀.     

赤泥矿中的稀土元素测定方法的研究

对目前较常用的稀土元素的测定方法进行了综述,分别探讨了各方法的优缺点.并着重研究了采用ICP-AES（电感耦合等离子体发射光谱仪）来测定赤泥矿中的15种稀土元素的方法,进行了一系列实验,结果表明,该方法用来检测稀土元素可行有效、方便快捷、精密度高.     

稀土元素对T_（10）钢冲击韧性和断口形貌的影响

本文研究了添加稀土元素的Ｔ（１０）钢冲击性能和断口形貌的关系。试验表明，在Ｔ（１０）钢中添加稀土元素对硬度没有明显的影响，但能显著改善该钢的冲击韧性。对稀土改善Ｔ（１０）钢冲击韧性和断口形貌的原因进行了初步讨论。