Effect of Texture and Grain Size on Bio-Corrosion Response of Ultrafine-Grained Titanium

The bio-corrosion response of ultrafine-grained commercially pure titanium processed by different routes of equal-channel angular pressing has been studied in simulated body fluid. The results indicate that the samples processed through route B_c that involved rotation of the workpiece by 90 deg in the same sense between each pass exhibited higher corrosion resistance compared to the ones processed by other routes of equal-channel angular pressing, as well as the coarse-grained sample. For a similar grain size, the higher corrosion resistance of the samples exhibiting off-basal texture compared to shear texture indicates the major role of texture in corrosion behavior. It is postulated that an optimum combination of microstructure and crystallographic texture can lead to high strength and excellent corrosion resistance.     

热处理工艺对冷轧热镀锌双相钢组织与性能的影响

在实验室试制了热镀锌冷轧DP590双相钢,分析了临界区退火温度对双相钢组织性能的影响,并将同种成分的实验室试制双相钢与工业生产双相钢的组织性能作对比,结果表明：热镀锌双相钢在镀锌段易出现贝氏体组织,且随临界区温度的上升,贝氏体组织含量增多,双相钢的强度上升,而塑性下降;工业试制双相钢,贝氏体和马氏体交互附着在铁素体晶界上,它们的体积分数约占29%,抗拉强度为610MPa,伸长率为31.5%,各项性能符合要求。研究得出,通过控制第二相（马氏体＋贝氏体）体积分数和分布形态,能够充分改善热镀锌双相钢的力学性能。     

可逆式冷轧对钢板织构及铁素体晶粒尺寸的影响

在实验室通过可逆式和连续式冷轧及退火模拟试验,研究了可逆式冷轧对DX51D（低碳铝镇静钢）和DX54D（无间隙原子钢）钢板织构及铁素体晶粒尺寸的影响。试验结果表明：①可逆式冷轧态试样α取向线{115}、{335}织构密度明显大于冷连轧试样,可逆式与连续式冷轧态试样γ取向线{111}织构密度无明显差别;②DX54D可逆轧制退火态试样γ取向线{111}织构密度大于冷连轧试样,其α取向线织构密度则与冷连轧试样相当;③DX51D可逆轧制退火态试样织构密度与冷连轧试样相当;④可逆轧制退火态试样的铁素体晶粒尺寸小于冷连轧试样。     

0018Ni循环相变过程对性能及晶粒显示的影响

研究0018Ni管材循环相变过程中组织、性能变化趋势,找出挤压后的热处理工艺对成品管性能及晶粒大小的影响关系;找到了导致化学腐蚀与电解腐蚀的晶粒形态差异的本质原因是热处理过程循环相变不充分。这种不充分明显降低性能指标,尤其是塑性指标。     

可逆式冷轧对钢板织构及铁素体晶粒尺寸的影响

在实验室通过可逆式和连续式冷轧及退火模拟试验,研究了可逆式冷轧对DX51D(低碳铝镇静钢)和DX54D(无间隙原子钢)钢板织构及铁素体晶粒尺寸的影响。试验结果表明:(1)可逆式冷轧态试样α取向线{115}、{335}织构密度明显大于冷连轧试样,可逆式与连续式冷轧态试样γ取向线{111}织构密度无明显差别;(2)DX54D可逆轧制退火态试样γ取向线{111}织构密度大于冷连轧试样,其α取向线织构密度则与冷连轧试样相当;(3)DX51D可逆轧制退火态试样织构密度与冷连轧试样相当;(4)可逆轧制退火态试样的铁素体晶粒尺寸小于冷连轧试样。     

Effect of Nucleant Particle Agglomeration on Grain Size

Metallurgical and Materials Transactions A - Solute accumulation/depletion in the liquid around a growing solid particle during the solidification of metallic melts creates a constitutionally...     

拉拔工艺对热镀锌钢丝性能的影响

介绍了拉拔工艺热镀锌钢丝σ、δ和扭转性能的影响,指出合理的拉拔工艺能改善热镀锌钢丝的综合力学性能。     

Correlation Between Texture,Grain Boundary Constitution,and Corrosion Behavior of Ni-Cu Coatings

Metallurgical and Materials Transactions A - Nickel-Copper (Ni-Cu) coating with different Cu contents (2 to 7 wt pct) was electrodeposited over a mild steel substrate. Corrosion properties...     

硼对低碳钢晶粒尺寸的影响

研究了硼对低碳钢晶粒尺寸的影响,结果表明:低碳钢中酸溶硼([B]s)的质量分数大于0.005%时,随酸溶硼的质量分数增加,铁素体晶粒尺寸明显变大.主要原因为硼的加入使钢的奥氏体晶粒增大,从而使铁素体晶粒尺寸变大;硼的加入抑制铁素体形核并降低相变开始的实际温度,孕育期变长,从而使铁素体晶粒尺寸变大.冷却速度为0.5～5℃/s,随冷却速度加快,晶粒尺寸明显减小;冷却速度为5～15℃/s,晶粒尺寸的变化不大.冷却速度大于5℃/s时,含硼低碳钢明显出现贝氏体,因此热轧后盘条的冷却速度最好控制在5℃/s以下.     

Effect of Crystallographic Texture on Anisotropy of Yield Strength in X100 Pipeline Steel

The anisotropy of microstructures and mechanical properties in commercial American Petroleum Institute (API) X100 pipeline steel was systematically investigated by experimental measurements. The experimental results show that anisotropy of yield strength could be observed considerably, which should be attributed to the crystallographic textures due to deformation and transformation of texture components. This is because the effect of the inhomogencity of microstructure in different directions on the mechanical properties could be reasonably neglected based on the experimental investigation of grain size distribution. The effect of crystallographic texture on the anisotropy of yield strength was interpreted theoretically based on the relationship between yield strength and average orientation factor.     

退火与平整工艺对热镀锌深冲钢力学性能的影响研究

作为汽车及家电用钢重要组成部分的热镀锌深冲钢板,因其良好的冲压性能已得到广泛地应用。基于薄板坯连铸连轧工艺(CSP)所提供的超低碳钢原料,通过在马钢2号热镀锌机组进行不同退火温度、不同TV值以及不同的平整和拉矫延伸率试验,研究了其对产品力学性能的影响。在此基础上提出了采用IF钢而不采用超低碳钢作为2号热镀锌机组深冲钢原料的建议。     

WC粉末粒度与形貌对硬质合金中WC晶粒度、晶粒形貌与合金性能的影响

探讨了粗颗粒与特粗颗粒两种粒度级别以及平面化表面与球化表面两种形貌特征的WC原料对WC-Co硬质合金中WC晶粒度、晶粒形貌以及合金性能的影响。结果表明,分别采用费氏粒度为11.4￣13.4μm,与22.0￣28.3μm两种粒度级别的WC粉末为原料制备合金,尽管两种合金硬度之间存在明显差别,但是两种合金的晶粒度相差很小,在4.0￣4.3μm之间,同属一种粒度级别。WC原料的原始形貌对合金中WC晶粒形貌与合金性能影响很小,碱金属掺杂原料制备的合金中WC晶粒结晶完整性相对较差。因此,高纯原料是制备高性能硬质合金的基础。     

电极端面尺寸对IF钢镀锌板点焊性能的影响

对DX54D冷轧IF钢镀锌板进行点焊试验,研究了焊接工艺参数及电极端面尺寸对镀锌板点焊性能、焊点拉剪性能及熔核尺寸的影响。结果表明:随着焊接电流的增加,焊点的拉剪强度和熔核尺寸均增大,当电流过大而发生飞溅时,焊点的拉剪强度和熔核尺寸开始降低。随着电极端面半径的减小,电极与工件的实际接触面积减小,引起电流密度升高,导致在相同焊接时间条件下得到相同熔核尺寸和焊点拉剪强度所需焊接电流降低。     

Ti含量和轧制工艺对AH36奥氏体晶粒大小的影响

本文利用Gleeble－1500热模拟试验机,研究了Ti含量对Ah36钢粗化温度的影响,同时利用二辊轧机研究了轧制温度、变形量对AH36钢的奥氏体晶粒大小的影响。该钢合理的加热温度范围为1200－1250℃。在轧制温度一定时,加大变形量,奥氏体晶粒尺寸减小;钛含量增加,奥氏体晶粒尺寸减小。     

Effect of Prior Austenite Grain Size on the Morphology of Nano-Bainitic Steels

Metallurgical and Materials Transactions A - The strength in nanostructured bainitic steels primarily arises from the fine platelets of bainitic ferrite embedded in carbon-enriched austenite....