HYDROGEN TRAPPING EFFECT OF SUBSTITUTIONAL ALLOYING ELEMENTS IN α-Fe

用电化学渗氢方法测定了氢在纯Fe和Fe-Cr,Mn,Co,Si,Mo的二元合金中的扩散系数。结果表明所研究的二元铁基合金中,随着合金元素浓度的增加,氢的扩散系数降低,氢的扩散激活能增加。根据Oriani模型计算了各种合金元素的氢陷阱参数,并获得了相应的氢与陷阱结合能。按陷阱结合能由小到大的顺序是:Si,Co,Ni,Mn,Cr和Mo。最后根据合金元素引起的晶格应变场与氢的弹性交互作用和合金元素与氢的电性交互作用对结合能的本质进行了分析。     

Effect of Mn and MnS on corrosion properties of domestic pipeline steels and welds

Base metals of domestic pipeline steels were used to study the effect of Mn on corrosion properties of SSCC( Sulfide Stress Corrosion Cracking), and welds were carried out to study the effect of MnS on corrosion properties of HIC ( Hydrogen Induced Cracking) both in solutions with wet hydrogen sulfide ( H2 S ). They were respectively conducted by referring to the standards of SSCC and HIC. Testing results revealed that with the increase of content Mn, the resistance of SSCC will be decreased, from the point of metallurgic view, and it is Mn element not C element to lead to the testing results of SSCC. Meanwhile, even under the condition without inclusions MnS, HIC in welds still occurred. That is to say, MnS is not necessary for HIC, the presence of local banded structures in which Mn and P are inclined to aggregate cause to the phenomena of HIC.     

多程序点焊控制器的研制

本文主要介绍了多程序点焊控制箱的程序过程以及主控制器及调制器的工作原理，并采用了一种新型的触发电路代替传统的脉冲变压器，具有触发可靠、大功率、高精度、电路简单等特点。     

INFLUENCE OF RESIDUAL STRESS AND SURFACE MORPHOLOGY ON FATIGUE PROPERTIES OF STEEL 60Mn

Influence of residual stress and surface morphology induced by shot-peening on fatigue behav-ior of a medium temperature tempered spring steel 60 Mn has been studied.The compressiveresidual stress induced in the near-surface region may improve fatigue limit from 930 to 1010MPa,and the very high tensile residual stress in the interior may reduce it from 1010 to 940MPa,whereas the severe surface damage may cause a drop-off of it from 1010 down to 800MPa.Fatigue cracks initiated in such position where the equivalent Mises stress,includingresidual stress,exceeded the local strength of the material.The compressive residual stress,induced by shot-peening,may intensify the effect of crack closure,so as to decrease the crackgrowth rate.     

SOME THERMODYNAMIC PROPERTIES IN PROCESS OF THERMAL REDUCTION OF Mg WITH HIGH AI ALLOY

本文以含高Al(Al76％,Si18.9％,Fe5.1％)的Al-Si-Fe合金为还原剂,在不同温度下进行热法还原Mg实验,测定了Mg的蒸气压为lgp_(Mg)=-8853/T+10.58.与用Si-Fe还原剂相比,在相同的p_(Mg)下,还原温度可下降约200℃。 用Bonnier法和本实验所测定的数据计算了Al-Si-Fe合金在不同温度下各组元的活度。结果表明,三元系中各组元活度均有负偏差,尤其Fe的偏差很大。另外,由以上所得的活度数据还计算了还原反应的平衡常数和热焓,分别为: lgK_[Al]=-18.40×10~4/T+117.2,ΔH=3529.5KJ     

PORTEVIN-LE CHATELIER EFFECT IN COMMERCIAL AI-Cu-Mg ALLOY

在一定的温度和应变速率范围内研究了淬火和淬火后经短期人工时效处理的Al-Cu-Mg合金薄板的Portevin-Le Chatelier效应.结果表明,淬火后短期人工时效处理可以推迟产生波纹痕迹.据此,提出了推迟板材产生不均匀变形带的措施.     

SOME EXPERIMENTS ON THE PURIFICATION OF ALUMINUM AND TIN BY THE ZONE-MELTING METHOD

<正> 用作半导体材料的锗和硅,需要高度纯化方能使用,已为众所周知。在研究金属的许多物理性质方面,如结晶凝固的过程,金属的强度、腐蚀及内部原子的扩散,合金的相图等,也常常需要先有纯金属或“纯合金”,方能进一步控制其他条件,系统地研究它们之间相应的规律。     

零电阻温度85.3K的Bi系氧化物超导体

用快淬工艺成功地制成起始转变温度112K、零电阻温度85.3K的Bi-Sr-Ca-Cu新型氧化物超导体.样品在84.0 K附近呈现明显的抗磁效应.     

COMPOSITION DESIGN AND EXPERIMENTAL STUDY OF SINGLE CRYSTAL ALLOY DD3

本文用渡辺提出的合金设计法进行正交设计计算,并用实验进行验证,最后确定出一种高温性能比较好的单晶合金DD3.其成分可保证具有约60wt-％的γ’相.良好的组织稳定性和优越的综合性能.     

水陆装甲车车体锈层分析

采用x射线衍射、SEM和EPMA等方法对服役20年～30年 水陆装甲车车体锈层进行了研究，研究表明：锈层中含有Cl-，锈层主要由α-FeOOH、β-FeOOH、γ-FeOOH、γ-Fe2O3、Fe3O4以及α-Fe等相组成，同时还残留有极少量的绿锈GR*(I).结合水陆装甲车的使用环境(海水、淡水，干湿交替)，对锈层各相的成因进行了分析.内锈层致密，大蚀坑下有小蚀坑，锈层中包含有呈小岛状弥散分布的Fe基体，均匀腐蚀与局部点蚀共同造成了材料的腐蚀破坏.