Research of the Continuous Casting Slab Transverse Cracking During Retarded Cooling Process

In this paper, the reason of 50Mn2V transverse cracking is studied by optical metallographic, SEM and in situ analysis system. Results show that the pearlite is surrounded by the net‐like pro‐eutectoid ferrite which locates at the former austenite grain boundary, the hydrogen content (ca.2 × 10^?4 wt%) exceeds the critical solubility in room temperature structure, divers types, and sizes inclusions (10–100 µm), plenty of fissures (2–50 µm) and classical cleavage fracture surface are obviously observed, meanwhile, a great degree of elements segregation (P, S, V, Ni, Cr correspond to 1.757, 1.674, 1.729, 1.475, 1.195, respectively) and a poorly 0.9283 integral density exist in this blank. From the above, internal gas pressure should be the dominant factor that leads the transverse embrittlement, while internal stresses, element segregation, and defects play an ancillary role.     

18Mn2CrMoBA薄钢板的焊接变形分析与防止技术

本文通过对18Mn2CrMoBA材料性能的分析,结合生产实际,制定出合理的焊接工艺措施,满足了设计和使用要求。     

37Mn5钢J55钢管混晶分析

混晶组织会影响钢管产品的性能。结合生产３７Ｍｎ５钢Ｊ５５油井用管的组织性能分析，指出了Ｊ５５钢管产生混晶组织的工艺原因， 提出了预防和改善的措施     

掺锰钛酸钡PTC陶瓷的制备工艺及其阻温特性研究

着重研究了掺锰钛酸钡ＰＴＣ陶瓷复合材料的优化制备工艺，测试不同掺锰浓度样口的阻温特性，分析掺锰浓度和测试电阻频率对材料阻温特性的影响，应用Ｗ．ＨｅｙＷａｎｇ模型说明高掺杂，高测试电场频率和低掺杂，低测试电场频率处阻温特性曲线中出现的电阻率双峰现象。     

连城锰矿资源特点及利用探讨

介绍福建省连城锰矿资源特点并从其手探讨综合回收利用的途径。     

炭基锌锰铜煤气脱硫剂的硫化行为研究

对锌、锰、铜摹单金属和复合金属氧化物脱硫剂的脱硫性能进行了讨论,并对炭材料作为脱硫剂和载体的研究现状进行了分析,同时对活化半焦作为脱硫剂载体的可行性进行了探讨.认为复合金属氧化物脱硫剂能够发挥单氧化物的优势,并克服其不足.将复合金属氧化物负载于炭材料上,可提高金属氧化物活性组分的利用率,改善脱硫剂的硫化性能,同时降低脱硫剂成本,使炭基锌锰铜复合金属氧化物煤气脱硫剂具有广阔的应用前景.     

Influence of Manganese and Nickel on the α´ Martensite Transformation Temperatures of High Alloyed Cr‐Mn‐Ni Steels

The martensite start temperature (M_s), the martensite austenite re‐transformation start temperature (A_s) and the re‐transformation finish temperature (A_f) of six high alloyed Cr‐Mn‐Ni steels with varying Ni and Mn contents in the wrought and as‐cast state were studied. The aim of this investigation is the development of the relationships between the M_s, A_s, A_f, T₀ temperatures and the chemical composition of a new type of Cr‐Mn‐Ni steels. The investigations show that the M_s, A_s and A_f temperatures decrease with increasing nickel and manganese contents. The A_f temperature depends on the amount of martensite. Regression equations for the transformation temperatures are given. The experimental results are based on dilatometer tests and microstructure investigations.     

Thermodynamic Evaluation of Inclusions Formation and Behaviour in Steels during Casting and Solidification

For demanding applications high steel cleanliness and strictly controlled inclusions are required. Primary inclusions are formed during steel treatments in the ladle. Most of these are removed to the ladle slag or on the lining. However, the rest of the inclusions still remain through the successive process stages, and additionally new inclusions are formed during casting and solidification due to decreasing thermodynamic solubility of oxygen in the steel at lower temperatures, reactions with surrounding slag, refractory materials and eventual contact with air. Inclusions formation and transformation are simulated by thermodynamic calculations in the steel/inclusions/slag system taking into account the solidification phenomena. In this paper inclusions in Si/Mn‐deoxidised steel and Al‐deoxidised Ca‐treated steels are contributed. Calculations are compared with experimental results from steel plants.     

Cr6Mn13Ni10／Cr5Mo异质接头时效过程中碳的扩散行为

Ｃｒ６Ｍｎ１３Ｎｉ１０／Ｃｒ５Ｍｏ异质金属焊接接头在时效过程中，其熔合区域的扩散行为不同于以往的Ａ／Ｆ异质焊接接头，时效初期奥氏体钢一侧有一定宽度的增碳层，随时效时间延长，增碳层反而逐渐变窄；时效温度越高，上述现象越明显，经７００℃，时效５０ｈ后增碳层可完全消失。     

Preparation,electrochemical performance and phase transition of high voltage LiNi0.5Mn1.5O4 cathode material

尖晶石LiNi_0.5Mn_1.5O₄因其可在4.7 V高电位下工作并有良好的循环特性,已成为最具潜力的高能量密度锂离子电池正极材料。本文首先采用喷雾干燥辅助烧结法制备了LiNi_0.5Mn_1.5O₄正极材料,考察了热处理条件对材料结构与性能的影响。用XRD、SEM和FT-IR等技术对所制备的LiNi_0.5Mn_1.5O₄材料的结构和表面形貌进行表征,利用原位XRD技术研究了LiNi_0.5Mn_1.5O₄正极材料在充放电过程中结构相变规律。结果表明,所制备的LiNi_0.5Mn_1.5O₄材料均具有Fd-3m空间群的立方相尖晶石型结构,并具有优异的电化学性能,其0.1 C时首次放电容量为132 mA·h/g,首轮库仑效率93.48%,高倍率下该材料的电化学性能优越。原位XRD测量结果分析表明,尖晶石型LiNi_0.5Mn_1.5O₄材料在充电过程中存在4个显著的相变过程,在嵌脱锂过程中,从四面体相向立方相结构相变过程是可逆的。