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Influence of rare earth Ce on hot deformation behavior of as-cast Mn18Cr18N high nitrogen austenitic stainless steel 被引量:4
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作者 Yushuo Li Yanwu Dong +3 位作者 Zhouhua Jiang Qingfei Tang Shuyang Du Zhiwen Hou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期324-334,共11页
The hot deformation behavior of Mn18Cr18N and Mn18Cr18N+Ce high nitrogen austenitic stainless steels at 1173-1473 K and 0.01-1 s^(-1) were investigated by thermal compression tests.The influence mechanism of Ce on the... The hot deformation behavior of Mn18Cr18N and Mn18Cr18N+Ce high nitrogen austenitic stainless steels at 1173-1473 K and 0.01-1 s^(-1) were investigated by thermal compression tests.The influence mechanism of Ce on the hot deformation behavior was analyzed by Ce-containing inclusions and segregation of Ce.The results show that after the addition of Ce,large,angular,hard,and brittle inclusions(TiN-Al_(2)O_(3),TiN,and Al_(2)O_(3)) can be modified to fine and dispersed Ce-containing inclusions(Ce-Al-O-S and TiN-Ce-Al-O-S).During the solidification,Ce-containing inclusions can be used as heterogeneous nucleation particles to refine as-cast grains.During the hot deformation,Ce-containing inclusions can pin dislocation movement and grain boundary migration,induce dynamic recrystallization(DRX)nucleation,and avoid the formation and propagation of micro cracks and gaps.In addition,during the solidification,Ce atoms enrich at the front of solid-li-quid interface,resulting in composition supercooling and refining the secondary dendrites.Similarly,during the hot deformation,Ce atoms tend to segregate at the boundaries of DRX grains,inhibiting the growth of grains.Under the synergistic effect of Ce-containing inclusions and Ce segregation,although the hot deformation resistance and hot deformation activation energy are improved,DRX is more likely to occur and the size of DRX grains is significantly refined,and the problem of hot deformation cracking can be alleviated.Finally,the microhardness of the samples was measured.The results show that compared with as-cast samples,the microhardness of hot-deformed samples increases signific-antly,and with the increase of DRX degree,the microhardness decreases continuously.In addition,Ce can affect the microhardness of Mn18Cr18N steel by affecting as-cast and hot deformation microstructures. 展开更多
关键词 rare earth hot deformation Mn18Cr18N steel non-metallic inclusions element segregation MICROHARDNESS
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Influence of Rare Earth Elements on Microstructure and Mechanical Properties of Cast High-Speed Steel Rolls 被引量:17
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作者 王明家 穆松梅 +1 位作者 孙菲菲 王艳 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第4期490-494,共5页
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... 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. 展开更多
关键词 eutectic carbide impact toughness differential scanning calorimetry high-speed steel roll rare earths
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Effects of Rare Earths on Toughness of 31Mn2SiRE Wear- Resistance Cast Steel 被引量:10
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作者 谢敬佩 王爱琴 +2 位作者 王文焱 李继文 李洛利 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期401-404,共4页
The toughness of 31Mn2SiRE wear-resistance cast steel were increased by means of RE compound modification and high temperature austenitizing. The results show that the microstructures can be refined, needle and networ... The toughness of 31Mn2SiRE wear-resistance cast steel were increased by means of RE compound modification and high temperature austenitizing. The results show that the microstructures can be refined, needle and network ferrite are eliminated, the dislocation density and the quantity of dislocated martensite are increased remarkably, and the shape and distribution of inclusions are improved by the addition of RE. Therefore, the mechanical properties of the modified steel can be greatly increased, especially the toughness (αK) by 44%, yield strength (σs) by 10%, and elongation (δ5) by 42%. 展开更多
关键词 31Mn2SiRE cast steel wear-resistance steel mechanical properties rare earths
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Effect of rare earths on mechanical properties of plasma nitrocarburized surface layer of 17-4PH steel 被引量:7
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作者 刘瑞良 闫牧夫 吴丹蕾 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第6期1056-1061,共6页
The aim of this investigation is to reveal the influence of rare earths(RE) addition on mechanical properties of plasma nitrocarburized 17-4PH steel.The nitrocarburized layers were characterized by optical microscope,... The aim of this investigation is to reveal the influence of rare earths(RE) addition on mechanical properties of plasma nitrocarburized 17-4PH steel.The nitrocarburized layers were characterized by optical microscope,scanning electron microscope equipped with energy dispersive X-ray analyzer,X-ray diffractometer,microhardness tester and pin-on-disc tribometer.The results showed that RE atoms could diffuse into the surface layer of 17-4PH steel plasma nitrocarburized at 500 °C for 4 h and did not change the ... 展开更多
关键词 17-4PH steel plasma nitrocarburizing mechanical properties rare earths
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Role of Rare Earth in Low Sulphur Nb-Ti-Bearing Steel 被引量:5
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作者 朱兴元 林勤 +3 位作者 曾静 刘继雄 高平祥 王跃华 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第1期81-85,共5页
The effect of rare earth on the microstructures, mechanical properties and inclu sions in low sulphur Nb-Ti-bearing steel were investigated. It is shown that t h e transverse yield point, the traverse tensile strength... The effect of rare earth on the microstructures, mechanical properties and inclu sions in low sulphur Nb-Ti-bearing steel were investigated. It is shown that t h e transverse yield point, the traverse tensile strength and elongation of testin g steels decrease initially and then rise with increasing content of rare earth. The impact energy values of the testing steels exhibit a contrary trend. Proper amount of rare earth in the steels can improve the anisotropy of impact toughne ss above -20 ℃ and it does not affect the type of microstructures which ar e st ill composed of ferrites and pearlites, but the pearlite amount increases. On one hand, rare earth cleans the molten steel and reduces the amount of inclusions; on the other hand, rare earth makes the inclusions spheroidizd, refi ned and dispersed, and thus improves the distribution of inclusions. 展开更多
关键词 metal materials Nb-Ti-bearing steel prop erty microstructure INCLUSION rare earths
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Control of nonmetallic inclusions of non-oriented silicon steel sheets by the rare earth treatment 被引量:13
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作者 ZHANG Feng MA Changsong +3 位作者 WANG BO ZHANG Peili MA Zhigang ZHANG Yi 《Baosteel Technical Research》 CAS 2011年第2期41-45,共5页
Based on the industrial production of non-oriented silicon steel, the rare earth (RE) treatment during the Ruhrstahl Heraeus (RH) refining process was studied. The morphology and the size distribution were observe... Based on the industrial production of non-oriented silicon steel, the rare earth (RE) treatment during the Ruhrstahl Heraeus (RH) refining process was studied. The morphology and the size distribution were observed for the steel specimens treated with different RE treatment conditions. Furthermore, the formation and change of the nonmetallic inclusion characteristics of finished steel sheets after the RE treatment were discussed. The results have shown that in the present work,the suitable RE metal additions are 0.6 -0.9 kg/t steel. After the suitable RE treatment,the formation of AIN and MnS inclusions were restrained, and the aggregation, flotation and removal of nonmetallic inclusions were efficiently promoted and the cleanliness of liquid steel was significantly increased. Meanwhile, the total oxygen concentration reached the minimum value and thle desulfurization efficiency was optimal ,and the type of main inclusions was approximately spherical or elliptical spherical RE radicle inclusions whose size was relatively large. 展开更多
关键词 non-oriented silicon steel Ruhrstahl Heraeus (RIt) refining rare earth (RE) treatment nonmetallic inclusions
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Effect of Rare Earth Composite Modification on Microstructure and Properties of a New Cast Hot-Work Die Steel 被引量:3
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作者 关庆丰 方建儒 +1 位作者 姜启川 王树奇 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第3期368-371,共4页
The effects of RE modification on structure and the properties of a new cast hot work die (CHD) steel were investigated. The grains of the CHD steel are refined by RE modification. With the increase of RE addition, b... The effects of RE modification on structure and the properties of a new cast hot work die (CHD) steel were investigated. The grains of the CHD steel are refined by RE modification. With the increase of RE addition, both grain size and inclusion amount are reduced. Appropriate amount of RE results in decrease in inclusion amount and formation of spheroidal inclusions uniformly-distributed in steel, so that the morphology and distribution of inclusions are improved. RE composite modification favors the formation of bainite, austenite and fine lath martensite with dense dislocation. When the residual RE content reaches 0.02%, no obvious changes in strength and hardness are found, while fracture toughness and threshold of fatigue crack growth are increased. The impact toughness, elongation and reduction of cross sectional area are increased by a factor of two, and thermal fatigue resistance is also improved. 展开更多
关键词 metal materials modification cast hot work die steel thermal fatigue rare earths
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Accelerating Effect of Rare Earth in Steel on Its Surface-Carburizing Process 被引量:2
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作者 袁泽喜 余宗森 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第1期50-53,共4页
The carburization of steel type 20 with and without RE addition was investigated. The results show that RE in steel can accelerate carburizing process at 850 and 910 ℃. The optimum RE content in steel is about 0 032... The carburization of steel type 20 with and without RE addition was investigated. The results show that RE in steel can accelerate carburizing process at 850 and 910 ℃. The optimum RE content in steel is about 0 032%. The mechanism of enhancing effect of RE on carburizing process was discussed. 展开更多
关键词 rare earths Low carbon steel CARBURIZATION KINETICS
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Effect of Rare Earths on Corrosion Resisting Properties of Carbon-Manganese Clean Steels 被引量:1
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作者 郭锋 林勤 孙学义 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第4期533-536,共4页
Electrochemistry experiments were made on carbon-manganese clean steel with rare earths Ce and La respectively to observe corrosion parameters such as corrosion current i_(corr), and characteristic potential of pittin... Electrochemistry experiments were made on carbon-manganese clean steel with rare earths Ce and La respectively to observe corrosion parameters such as corrosion current i_(corr), and characteristic potential of pitting E_b. The results indicate that the rare earths have effect on corrosion resisting properties of carbon-manganese clean steel, and the optimum contents of La is about 0.011% (mass fraction) and Ce about 0.014% (mass fraction) respectively. The change of corrosion resistance is related to the action of rare earths on microstructure and effect on surface state of samples in the process of polarization. 展开更多
关键词 metal material corrosion resistance carbon-manganese clean steel ELECTROCHEMISTRY rare earths
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Effect of Rare Earth (Niobium) on Costed and Hot-Rolled Microstructure and Properties of Heavy Rail Steels 被引量:1
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作者 Yu Ning Sun Zhenyan +3 位作者 Ji Jingwen Ren Xinjia Wang Yunsheng Wang Longmei 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第5期646-646,共1页
A compared investigation was made on the microstructure and mechanical properties of continuous casting square blanks of BNbRE and U71Mn heavy rail steels having eutectoid composition. The variation of solidified stru... A compared investigation was made on the microstructure and mechanical properties of continuous casting square blanks of BNbRE and U71Mn heavy rail steels having eutectoid composition. The variation of solidified structure of the square blanks was demonstrated by measuring hardness. The observation to the structure and inclusions in the head, waist and base of the hot-rolled rails of the test steels were carried out with optical microscope and SEM. It is found that the casting blanks of both tested steels compose of three areas with constant hardness and three hardness varying areas, and there is considerable P-eutectic structure in the blank of the U71Mn steel. The distribution of the inclusions in the UT1Mn steel rail is mainly oxides in both rail head and rail base, and is mainly MnS in the waist of the rail. There has strong effect of the addition of rare earth elements on them. The discussion on these results was made. 展开更多
关键词 rail steel niobimn microstructure and property rare earths
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High-Temperature Oxidation Behavior of 5Cr21Mn9Ni4N Steel Micro-Alloyed by Rare Earth 被引量:1
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作者 Yu Shichang Wu Shenqing +4 位作者 Gong Youjun Gong Yuansheng Lian Mingsheng Ye Gang Cheng Yijun 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第3期267-267,共1页
The oxidation resistance of 5Cr21Mn9Ni4N steel micro-alloying by RE at 700 - 900 ℃ was investigated. The results indicate that oxidation exponent n and oxidation activation energy are increased, and oxidation velocit... The oxidation resistance of 5Cr21Mn9Ni4N steel micro-alloying by RE at 700 - 900 ℃ was investigated. The results indicate that oxidation exponent n and oxidation activation energy are increased, and oxidation velocity constant kp is decreased when 0.2% RE is added in 5Cr21Mn9Ni4N steel. The addition of RE elements does not alter phase constitution of oxidation scale, however it improves the configuration of oxidation scale, and increases thermal stability and adhesivity of oxidation scale, which results in the raise of oxidation resistance of 5Cr21Mn9Ni4N steel at high temperature. The oxidation scale constitutes of refractory steel transfer from manganic oxide mostly to ferric oxide mostly with the increase of temperature, which leads to descend of compactness and desquamation resistance of oxidation scale. The mass increase of ferric oxide in the oxidation scale and the looseness of oxidation scale are the main reason to descend the oxidation resistance of refractory steel. 展开更多
关键词 5Cr21Mn9Ni4N steel oxidation kinetics oxidation scale oxidation resistance rare earths
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APPLICATION OF RARE EARTH IN SURFACE HEAT TREATMENT OF HOT-WORKING DIE STEELS 被引量:1
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作者 胡正前 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1997年第Z1期138-145,共8页
This paper studies a compound treatment. i. e. liquid S , N,C co-diffusing with rare earth (RE) and then oxidization , for hot-working die steels , and the effect of RE on thermal fatigue behavior of the diffused laye... This paper studies a compound treatment. i. e. liquid S , N,C co-diffusing with rare earth (RE) and then oxidization , for hot-working die steels , and the effect of RE on thermal fatigue behavior of the diffused layer. XRD and SEM energy spectrum prove that trace RE element actually penetrates into the surface layer of steels. The result shows that RE can reduce the gradient of change of hardness in diffused layer, improve the morphology and distribution of compounds , and reduce the degree of surface alligator crack for thermal fatigue. The behavior of thermal fatigue of hot-working die steels is raised by 70% or so after the application of RE. The effect of RE is analysed according to the theory. 展开更多
关键词 rare earth chemical heat treatment hot -working die steel behavior of thermal fatigue.
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Analysis of Coating Microstructure of Hot-Dip Aluminum of Deformed Low-Carbon Steel Containing Rare Earth 被引量:1
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作者 范力茹 刘琳 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期460-463,共4页
The coating microstructure of hot-dip aluminum (HDA) of deformed low-carbon steel containing RE was analyzed by metallography microscopy, TEM and XRD, and the forming mechanism was also discussed. The results show tha... The coating microstructure of hot-dip aluminum (HDA) of deformed low-carbon steel containing RE was analyzed by metallography microscopy, TEM and XRD, and the forming mechanism was also discussed. The results show that, the Fe_2Al_5 phase, on whose subcrystal boundaries, Al particles with the size of 7~30 μm existing on parallel linear are, grows a strong orientation. And the spread activation energy of Al is 155.22 kJ·mol -1. In addition, the effects of deformation on coating microstructure of hot-dip aluminum and the function of RE were preliminarily analyzed. 展开更多
关键词 deformed low-carbon steel hot-dip aluminum (HDA) the coating microstructure rare earths
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Influence of Rare Earth on Property of Low Chromium Semi-Steel 被引量:1
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作者 LIUJian-hua XIEDan-yang +2 位作者 LIChang-sheng SHAOLi ZHANGRui-jun 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2003年第3期50-53,共4页
The influence of rare earth( RE) content on mechanical properties and abrasion resistance of low chromium semi-steel was studied by means of metallographic examination,scanning electron microscopic examination and mec... The influence of rare earth( RE) content on mechanical properties and abrasion resistance of low chromium semi-steel was studied by means of metallographic examination,scanning electron microscopic examination and mechanical property test. The experiment results show that RE can improve the comprehensive properties,especially in combination with proper heat treatment. The optimum properties of low chromium semi-steel modified by RE of 0. 25 % could be obtained by normalization at 950 ℃ for 3 h. The main reason is the change in morphology and distribution of eutectic carbide and the precipitation of granular carbides. 展开更多
关键词 rare earth low chromium semi-steel eutectic carbide PRECIPITATION granular carbide
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EFFECTS OF RARE EARTH METALS ON MICROSTRUCTURAL TRANSFORMATION OF LOW OR MEDIUM CARBON Si-Mn-V STEELS DURING QUENCHING AND TEMPERING
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作者 WANG Xiaotian YAO Yinliang SHAO Tanhua Xi′an Jiaotong University,Xi′an,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1991年第3期188-193,共6页
The microstruetural transformation of steels:20SiMn2V,20SiMn2VRE,40SiMn2V and 40SiMn2VRE during quenching and tempering have been examined by TEM,X-ray diffraction and dilatometer.It was shown that the addition of rar... The microstruetural transformation of steels:20SiMn2V,20SiMn2VRE,40SiMn2V and 40SiMn2VRE during quenching and tempering have been examined by TEM,X-ray diffraction and dilatometer.It was shown that the addition of rare earth metals not only can refine the austenite grains of the low or medium carbon steels and packet of lath martensite and lath size,lower the M_s temperature,but can also raise the relative percentage of disloca- tion substructure of martensite in medium carbon steel,but there is little effect on volume frac- tion and thermal stability of retained austenite quenching and tempering structure of low or medium carbon steels.The rare earth metals may remarkably inhibit the decomposition of low carbon martensite during low temperature tempering,retard the precipitation of cementite plates in lath grains and delay the spheroidization of carbides.They may also restrain obvious- ly the precipitation and spheroidization of cementite in medium carbon martensite during high temperature tempering. 展开更多
关键词 rare earth metals TEMPERING SiMnV steel microstrueture
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Kinetics Analysis of Pre-Eutectoid Transformation of Austenite in Carbon-Manganese Clean Steel with Rare Earths
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作者 郭锋 林勤 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S1期465-467,共3页
By means of rapid cool dilatometry, the influence of rare earths on kinetics of pre-eutectoid transformation of austenite of carbon-manganese clean steel was studied. While the content of rare earths were proper, the ... By means of rapid cool dilatometry, the influence of rare earths on kinetics of pre-eutectoid transformation of austenite of carbon-manganese clean steel was studied. While the content of rare earths were proper, the nucleation of pre-eutectoid ferrite on the grain boundary of austenite was accelerated and the incubation period of pre-eutectoid transformation was shortened. But while rare earths were excessive, opposite actions appeared. Rare earths decreased transformation velocity constant in the process of transformation from austenite to ferrite, which meant that the growth of per-eutectoid ferrite became slow. The reason above varieties was related to effect of rare earth on grain boundary constitution of austenite and diffusion of carbon element. 展开更多
关键词 clean steel per-eutectoid transformation KINETICS rare earths
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Effect of Rare Earth Elements on Thermal Fatigue Property of Low Chromium Semi-Steel
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作者 常立民 刘建华 +3 位作者 张瑞军 邵利 于升学 谌岩 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第2期172-175,共4页
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 mater... 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 3 h. 展开更多
关键词 metal materials low chromium semi steel thermal fatigue property rare earths
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Development and Application of a Heat-resistant Low Ni Steel Modified by Rare Earth for Furnace Roller
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作者 张庆登 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第1期51-56,共6页
The low Ni steel modified hy rare earth(3Cr24NiTSiN with an addition of 0.3% Ce)for furnace roller has been developed.Due to the RE(rare earth)addition,a dense oxide film is formed on the steel surface at high tempera... The low Ni steel modified hy rare earth(3Cr24NiTSiN with an addition of 0.3% Ce)for furnace roller has been developed.Due to the RE(rare earth)addition,a dense oxide film is formed on the steel surface at high temperature,and the oxidation rate is decreased.This film has so good adhesion to the matrix that it will not be peeled off easily.The RE modified steel has excellent oxidation resistance and thermal strength even if being used continuously for a long period at high temperature.This steel roller has a service life of about 4 years com- parable to high Ni steel ones,so the low Ni steel can replace high Ni steel to make furnace roller.The Ni content of this material can be reduced by 65% in comparison with Cr25Ni20Si2 steel,The low Ni steel has better pro- eessing properties including melting,casting and working properties than that of high Ni ones. 展开更多
关键词 rare earth Heat-resistant low Ni steel turnace roller
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Effects of Rare Earth Elements on Corrosive Wear Behaviour of Cast Cr-Mn-N Stainless Steel in Dilute Sulphuric Acid
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作者 丁晖 袁广银 +2 位作者 余刚 宋长琴 明照祥 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第3期47-52,共6页
The effects of rare earth elements on the corrosion and corrosive wear resistance of Cr Mn N stainless steel were studied, and the optimal content of RE(%) in the steel was obtained. This work would provide the nece... The effects of rare earth elements on the corrosion and corrosive wear resistance of Cr Mn N stainless steel were studied, and the optimal content of RE(%) in the steel was obtained. This work would provide the necessary parameters in producing this kind of stainless steel. 展开更多
关键词 rare earths Cr Mn N stainless steel Corrosive wear
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Layer Structure Analysis of Low-Carbon Steel Containing Rare Earth by High-Temperature Carburizing of Liquid Cast-Iron
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作者 谌岩 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第S1期130-133,共4页
The layer structure of low-carbon steel containing RE by high-temperature (T>1200 ℃) carburizing of liquid cast-iron was studied and the diffusion activation energy of carbon was calculated by metallographic micr... The layer structure of low-carbon steel containing RE by high-temperature (T>1200 ℃) carburizing of liquid cast-iron was studied and the diffusion activation energy of carbon was calculated by metallographic microscpe, chemical analysis etc. The result shows that the technology of carburizing in liquid cast-iron can expedite caburization distinctly and changes the carburizing layer structure. The carburizing rate is 60~80 times of that of the traditional technology, and there is about 43% decrease in the activation energy compared with gas-carburization. In outer structure layer, cementite is formed simultaneously both on the crystal boundary reticularly and inside the crystal grains stripedly. In inner carburizing layer, there is undissolved blocky ferrite in reticular cementite. Besides, rare earth element can expedite carburization process. 展开更多
关键词 low-carbon steel high-temperature carburizing of liquid cast-iron layer structure rare earths
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