耐磨锰钢中共晶体的球化

对Ｃｇ变质处理的奥氏体－贝氏体耐磨锰钢进行了热力学二维点阵错配度计算，采用ＴＥＭ和ＳＥＭ观察及电子探针分析，发现ＣａＳ可以作为共晶的异质核心而使晶体球化。     

团球状共晶体奥氏体-贝氏体钢抗冲击磨料磨损行为

采用ＴＥＭ，ＳＥＭ；电子探针和 ＭＤＬ－１０型动载磨料磨损实验机研究 Ｍｇ－Ｃｅ－ＡＩ复合变质团球状共晶体奥－贝钢（简称ＡＢＮＥ钢）复相组织的形成及抗冲击磨料磨损行为结果表明，钢中贝氏体组织由板条铁素体与残余奥氏体组成，团球状共晶体是（Ｆｅ， Ｍｎ）３Ｃ和奥氏体两相伪共晶组织 ＡＢＮＥ钢在中、低冲击工况下耐磨性优于奥－贝钢、奥－贝球铁、团球状碳化物中锰钢，其原因与国球状共晶体可有效地减轻磨料的侵入深度和阻碍微切削作用，以及磨损表面形成大量纳米晶粒和非晶态组织。在亚表层存在形变马氏体与形变贝氏体组织有关     

团球状巫晶体奥氏体——贝氏体钢抗冲击磨料磨损行为

采用ＴＥＭ,ＳＥＭ,电子探针和ＭＤＬ－１０型动载磨料磨损实验机研究Ｍｇ－Ｃｅ－Ａｌ复合变质团球状共晶体奥－贝钢（简称ＡＢＮＥ钢）复相组织的形成及抗冲击磨料磨损行为。结果表明,钢中贝工体组织由板条铁素体与残余奥氏体组成,团球状共晶体是（Ｆｅ,Ｍｎ）３Ｃ和奥氏体两相伪共晶组织。ＡＢＮＥ钢在中、低冲击工况下耐磨性优于奥－贝钢、奥－贝球铁、团球状碳化物中锰钢,其原因与团球状共晶体可有效地减轻磨料的侵入深度     

PHYSICO-CHEMICAL PROPERTIES OF NaF-AIF_3-BaCl_2-NaCl ELECTROLYTE SYSTEM

ＰＨＹＳＩＣＯ－ＣＨＥＭＩＣＡＬＰＲＯＰＥＲＴＩＥＳＯＦＮａＦ－ＡＩＦ３－ＢａＣ１２－ＮａＣＩＥＬＥＣＴＲＯＬＹＴＥＳＹＳＴＥＭＬｉ，Ｇｕｏｈｕａ；Ｌｉ，Ｄｅｘｉａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＮｏｍ－ｆｅｒｒｏｕｓＭｅｔａｌｌｕｒｇｙ，Ｎｏｒｔｂｅ...     

调整Si／C和（Si—Mn）差值用复合孕育处理方法提高灰铸铁强度

在冲天炉生产条件下，通过调整铁水的Ｓｉ／Ｃ和（Ｓｉ－Ｍｎ）值，采用炉前包内部锰铁，以ＲＥ－Ｂａ－Ｃａ和Ｓｉ－Ｃａ合金混合孕育剂，对灰铸铁铁水进行复合孕育处理，试验结果表明，在合适的Ｓｉ／Ｃ和（Ｓｉ－Ｍｎ）值条件下，复合孕育处理可使３．９％￣４．２５％ＣＥ的灰铸铁抗拉强度达到２５０ＭＰａ。     

GAS-LIQUID EQUILIBRIUM OF Pb-Cd-Zn SYSTEM UNDER VACUUM

ＧＡＳ－ＬＩＱＵＩＤＥＱＵＩＬＩＢＲＩＵＭＯＦＰｂ－Ｃｄ－ＺｎＳＹＳＴＥＭＵＮＤＥＲＶＡＣＵＵＭＧＡＳ－ＬＩＱＵＩＤＥＱＵＩＬＩＢＲＩＵＭＯＦＰｂ－Ｃｄ－ＺｎＳＹＳＴＥＭＵＮＤＥＲＶＡＣＵＵＭ￥Ｌｉｕ，Ｒｉｘｉｎ（ＩｎｓｔｉｔｕｔｅｏｆＣｈｅｍｉｃａ...     

AN INVESTIGATION ON PHASE DIAGRM OF TERNARY SYSTEM CeCl_3-BaCl_2-LiCl

ＡＮＩＮＶＥＳＴＩＧＡＴＩＯＮＯＮＰＨＡＳＥＤＩＡＧＲＭＯＦＴＥＲＮＡＲＹＳＹＳＴＥＭＣｅＣｌ＿３－ＢａＣｌ＿２－ＬｉＣｌＡＮＩＮＶＥＳＴＩＧＡＴＩＯＮＯＮＰＨＡＳＥＤＩＡＧＲＭＯＦＴＥＲＮＡＲＹＳＹＳＴＥＭＣｅＣｌ＿３－ＢａＣｌ＿２－ＬｉＣｌ￥Ｚｈ...     

HIGH-TEMPERATURE HEAT CAPACITIES OF THE PHASES IN Y-Ba-Cu-O SYSTEM

ＨＩＧＨ－ＴＥＭＰＥＲＡＴＵＲＥＨＥＡＴＣＡＰＡＣＩＴＩＥＳＯＦＴＨＥＰＨＡＳＥＳＩＮＹ－Ｂａ－Ｃｕ－ＯＳＹＳＴＥＭＺｈａｎｇＨｅｎｇｚｈｏｎｇ；ＦａｎｇＺｈｅｎｇ；ＺｈａｎｇＰｉｎｇｍｉｎ；ＣｈｅｎＸｉｎｍｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓ...     

Raman Study of Defects in SI－GaAs and Se－doped Epitaxial Layer Irradiated by 10 MeV Electrons

ＲａｍａｎＳｔｕｄｙｏｆＤｅｆｅｃｔｓｉｎＳＩ－ＧａＡｓａｎｄＳｅ－ｄｏｐｅｄＥｐｉｔａｘｉａｌＬａｙｅｒＩｒｒａｄｉａｔｅｄｂｙ１０ＭｅＶＥｌｅｃｔｒｏｎｓＷｕＦｅｎｇｍｅｉ，ＬｉＨａｉｆｅｎｇ，ＣｈｅｎＷｕｍｉｎｇ，ＣｈｅｎｇＧｕｎｇｘｕａｎｄＨ...     

奥－贝球铁中残余奥氏体含量的研究

用Ｘ射线衍射分析仪测定了Ｓｉ、Ｃｕ、Ｍｏ含量和等温淬火温度、保温时间对奥－贝球铁中残余奥氏体含量的影响规律，在ＳＥＭ下现在分析了残余奥氏体量对试样断裂方式的影响；结果表明，Ｃｕ使残余奥氏体含量提高，Ｍｏ使残余奥氏体含量降低。一定的淬火温度、保温时间和含Ｓｉ量，可使残余奥氏体含量具有最高值，奥氏体含量减少使断裂方式向脆性断裂转变。     

Fourier Thermal Analysis of the Eutectic Formed in Pb-Sn Alloys

The effect of the presence of two different primary phases on the microstructural characteristics and solidification kinetics of Pb-Sn eutectic was analyzed using Fourier thermal analysis method (FTA) and microstructural characterization. Three Pb-Sn alloys, a hypoeutectic, an eutectic, and a hypereutectic alloy, were melted in an electric furnace under an argon atmosphere and poured into sand molds. Cooling curves were obtained and numerically processed using FTA. Microstructural observations of the probes indicate a lamellar morphology for the eutectic microconstituent of the hypereutectic alloy; the eutectic alloy shows the presence of both lamellar and anomalous eutectic and the hypoeutectic alloy shows only the presence of anomalous eutectic. FTA results indicate that in the case of the probes showing the presence of anomalous eutectic, there is a primary eutectic formed during recalescence at high undercooling and a secondary eutectic yielded at low undercooling at the eutectic plateau temperature. This result shows that the cause behind the observed differences in the eutectic morphologies of the experimental alloys lies on the nucleating ability of the primary phase available as a potential substrate for nucleation of the eutectic microconstituent.     

Ag-Cu/Co-Sn共晶合金深过冷快速凝固反常共晶的形成研究

利用熔融玻璃净化循环过热的方法进行了Ag-Cu/Co-Sn共晶合金的深过冷快速凝固实验,并系统研究了熔体过冷度和微量Nb添加对反常共晶形成的影响。结果表明,快速凝固过程中共晶枝晶内部首先重熔形成反常共晶,随着过冷度的增大,共晶相的形貌从蠕虫状转变为球形颗粒,被重熔形成的固相颗粒将作为剩余液相形核生长的基底,Ag-Cu共晶中共晶两相形核具有非互惠性。Co-Sn共晶合金中添加Nb元素后样品内部反常共晶形成的临界过冷度由23 K降低至15 K,而表面组织中过冷度从45 K降低至30 K。由于样品表面与坩埚壁接触有利于结晶潜热消散,反常共晶形成的临界过冷度较高。Ag-Cu共晶合金温度再辉曲线上慢速凝固阶段持续的时间较Co-Sn共晶合金要长。     

Modeling of aluminum-silicon irregular eutectic growth by cellular automaton model

Due to the extensive application of Al-Si aloys in the automotive and aerospace industries as structural components, an understanding of their microstructural formation, such as dendrite and (Al+Si) eutectic, is of great importance to control the desirable microstructure, so as to modify the performance of castings. Since previous major themes of microstructural simulation are dendrite and regular eutectic growth, few efforts have been paid to simulate the irregular eutectic growth. Therefore, a multiphase celular automaton (CA) model is developed and applied to simulate the time-dependent Al-Si irregular eutectic growth. Prior to model establishment, related experiments were carried out to investigate the inlfuence of cooling rate and Sr modiifcation on the growth of eutectic Si. This CA model incorporates several aspects, including growth algorithms and nucleation criterion, to achieve the competitive and cooperative growth mechanism for nonfaceted-faceted Al-Si irregular eutectic. The growth kinetics considers thermal undercooling, constitutional undercooling, and curvature undercooling, as wel as the anisotropic characteristic of eutectic Si growth. The capturing rule takes into account the effects of modiifcation on the silicon growth behaviors. The simulated results indicate that for unmodiifed aloy, the higher eutectic undercooling results in the higher eutectic growth velocity, and a more reifned eutectic microstructure as wel as narrower eutectic lamelar spacing. For modiifed aloy, the eutectic silicon tends to be obvious ifbrous morphology and the morphology of eutectic Si is determined by both chemical modiifer and cooling rate. The predicted microstructure of Al-7Si aloy under different solidiifcation conditions shows that this proposed model can successfuly reproduce both dendrite and eutectic microstructures.     

微量Mg在M2高速钢中的作用

研究了Ｍｇ对Ｍ２高速钢凝固组织和共晶碳化物高温球化的影响，试验表明：加入适量的Ｍｇ可以使Ｍ２高速钢通常的片状Ｍ２Ｃ型共晶碳化物转变成鱼骨状的Ｍ６Ｃ和块状的ＭＣ型碳化物，Ｍｇ还阻碍鱼骨状共晶碳化物的高温球化。     

亚共晶Al-Si合金共晶团的形核与生长

采用光学显微镜、扫描电镜及电子背散射衍射技术研究亚共晶Al-Si合金共晶团的形核与生长。通过揭示共晶团和结晶位向的分析发现：在同一个共晶团中Si相和Al相都不是单晶体,而是由不同位向的小＂晶粒＂构成的。提出不能依据共晶团中Al相与周围初生枝晶Al相的位向关系来确定共晶的形核模式的建议。然而,初生枝晶铝相的演化显著影响随后的共晶形核与生长。涉及的杂质元素使共晶Si的形貌由粗大的片状转变成细小的纤维状的变质行为,可能与共晶的形核无关。     

Fe-Ni-P-B共晶合金的深过冷凝固组织演化

采用玻璃熔覆法使Fe-Ni-P-B共晶合金在不同过冷度条件下凝固,研究了其组织随过冷度的演化规律.结果表明,随着过冷度的增加,凝固组织形态逐渐从棒状规则共晶向不规则的粒状共晶组织转化.当T＜35 K时,棒状规则共晶组织随过冷度增加而逐渐细化;当35 K＜ T＜150 K时,凝固组织由团状非规则共晶与棒状规则共晶构成,且随着过冷度增加非规则共晶逐渐增多,规则共晶组织减少,共晶间距增大;当T＞150K时,获得完全非规则共晶组织.应用Jackson-Hunt共晶生长模型和枝晶熔断理论,对Fe-Ni-P-B共晶合金凝固组织形成机制进行了分析讨论.     

Sb变质后Al-Si合金共晶组织的不均匀性

为了研究Sb变质的Al-13Si-0.4Mg合金中共晶组织的不均匀性,采用液淬技术及光学显微镜考察Sb变质的Al-13Si-0.4Mg合金凝固过程中的组织形成过程。结果发现,在共晶反应初期,先期形成的共晶团的分枝很少,此时形成的共晶组织往往较粗大,表现为共晶Si片较厚、片间距大、分枝少;而此后的共晶反应过程中,共晶团的分枝增加,形成的共晶组织较细小,表现为共晶Si片较薄、片间距小、分枝密集。组织不均匀性的主要原因是Sb在共晶固/液界面前沿的富集程度不同,导致了Sb在共晶Si表面的吸附数量不同,从而影响了共晶Si的生长速度。     

Penetrating behavior of eutectic liquid during Al/Cu contact reactive brazing

1　ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｔｈｅｔｒａｄｉｔｉｏｎａｌｓｏｌｄｅｒｉｎｇｔｅｃｈｎｏｌｏｇｙ ,ｔｈｅ“ｂｉｇａｎｄｓｍａｌｌｅｎｖｅｌｏｐｉｎｇ”ｐｈｅｎｏｍｅｎｏｎｗｉｌｌｏｃｃｕｒｄｕｒｉｎｇｔｈｅｆｌｏｗｉｎｇｏｆｌｉｑｕｉｄｆｉｌｌｅｒｍｅｔａｌｉｎｔｈｅｆｉｌｌｅｔｓｏｔｈａｔｔｈｅｃｏｍｐａｃｔｎｅｓｓｏｆｔｈｅｓｅａｍｃｏｕｌｄｎｏｔｂｅａｓｓｕｒｅｄ[1] .Ａｔｂｅｇｉｎｎｉｎｇｏｆ 1970ｓ ,ｔｈｅｍｅｔｈｏｄｏｆｃｏｎｔａｃｔｒｅａｃｔｉｖｅｂｒａｚｉｎｇ (ＣＲＢ)ｗａｓｄｅｖ…     

电磁搅拌作用下形成分离共晶的研究

研究了近２０种简单和复杂二元共晶合金在强磁场搅拌下形成分离共晶的现象．发现大多数金属／非金属类共晶和部分金属／金属间化合物类共晶发生分离共晶现象，其判据可定为分离相的熔解熵△Ｓ≥２３Ｊ／（ｍｏｌ·Ｋ）．     

Effect of phosphor addition on eutectic solidification and microstructure of an Al-13％Si alloy

As the refiner or modifier, the master alloys containing high concentration phosphor are widely used in preparing eutectic or hypereutectic Al-Si alloys. To study the effect of phosphor addition on the eutectic solidification and microstructure of the Al-13%Si alloy, an investigation has been undertaken by means of thermal analysis and micro/macro-structure observation. Results indicate that addition of phosphor in near eutectic Al-Si alloy promotes the nucleation of eutectic but has little refinement impact on primary Si particles as expected. Conversely, both primary Si particles and eutectic Si flakes become slightly coarser in P-rich alloys. The coarsening of eutectic Si flakes ties closely to the increased eutectic growth temperature with phosphor addition. The eutectic solidification of the alloy proceeds from the near mold zone towards the center, and it is also found that a few independent nucleation regions emerge in liquid at the solidification front due to the addition of phosphor.