烟煤胶质层指数准确度的试验

介绍了烟煤胶质层指数的测定方法,分析了煤样粒度、装样量、升温速度等对烟煤胶质层指数测定的影响,对传统法与半自动法的胶质层指数测定准确度进行了试验,该试验结果准确,能满足邯钢焦化厂的生产需要。     

自动胶质层指数测定仪检测结果 影响因素的探讨

文中从自动胶质层指数测定原理、人工操作、工作环境、实验设备、测定使用压力大小、仪器程序等方面对HH-JCY/D全自动胶质层指数测定仪检测结果精密度影响因素进行探讨,提出提高HH-JCY/D全自动胶质层指数测定仪检测精密度的有效措施,减少因胶质层指数检测结果精密度对焦煤检测的及时率影响,对HH-JCY/D全自动胶质层指数测定仪的使用有较好的指导作用.     

8098单片机胶质层温度控制仪

胶质层控温仪是焦化厂用来测定胶质层指数所用的仪表，本文介绍了８０９８单片机胶质层控温仪的功能以及系统的硬件和软件结构．     

8098单片机胶质温度控制仪

胶质层控温仪是焦化厂用来测定胶质层指数所用的仪表，本文介绍了８０９８单片机胶质层控温仪的功能以及系统的硬件和软件结构。     

烟煤胶质层指数测量不确定度的评定

烟煤胶质层指数是一种表征烟煤塑性的指标,用胶质层的最大厚度Y值和最终体积收缩度X值来表示。为满足企业对烟煤胶质层指数检测结果可信度的要求,在实验室对胶质层指数的测量不确定度进行了评定。检验员通过对多组不同种类的烟煤样进行多次试验,分析了实验过程中各显著因素对测量不确定度的影响,并依据GB/T 479-2016检测方法计算出影响胶质层指数各种因素的标准不确定度。通过合成各种标准不确定度分量,最终得出测量结果的扩展不确定度。     

对烟煤胶质层指数的认识

在焦化生产中，烟煤的胶质层指数能指导配煤炼焦生产，在测定胶质层指数的试验过程中影响因素较多，准确测定Y值，找出Y值与G值的相关关系，总结体积曲线与焦块技术特征的联系，对昆钢炼焦生产有实际的指导作用。     

烟煤胶质体质量与全水分关系研究

通过比较不同水分、不同干燥条件下炼焦煤胶质层的变化情况,探索水分对炼焦煤结焦过程的影响.结果显示水分的变化不但对胶质层厚度Y值有一定影响,而且会稀释胶质体,影响胶质体的质量,具体表现在影响胶质层测定曲线.研究结果证明,烟煤水分高低对结焦过程的影响较大.     

炼焦用煤胶质层指数和奥亚膨胀度指标的局限性探讨

通过对国内外不同矿点炼焦煤变质程度、胶质层指数Y值、奥亚膨胀度b值、高温塑性、煤岩显微组分和成焦光学组织结构分析研究,发现变质程度、胶质层指数Y值和奥亚膨胀度b值相同或极其接近的炼焦煤高温塑性和单种煤成焦光学组织结构差异悬殊。其原因不在于镜质组含量的高低,而在于成因因素造成的镜质组性质不同。指出,胶质层指数和奥亚膨胀度指标在表征其结焦性时存在局限性,高温塑性和单种煤成焦光学组织结构对炼焦煤结焦性的科学评价至关重要。     

炼焦煤基氏流动度及相关性的研究

通过测定某焦化公司几种常用炼焦煤的基氏流动度,分析不同煤种的基氏流动度曲线差异,探索基氏流动度与粘结指数(G值)、最大胶质层厚度(Y值)之间的相关性,并指出基氏流动度在炼焦配煤中的作用。     

线性回归方程式在检测煤胶质层中的应用

应用线性回归方程测量煤的胶质层最大厚度值与粘结指数值之间相关关系。根据实际数据判断两者的强相关性,求得线性方程,用显著性方法检验了线性方程的成立。通过对线性回归方程的标准误差的概率值,证明胶质层最大厚度估算值具有较强的准确性。该方程可应用与煤胶质层测定过程,以及炼焦工艺快速配煤Y值的估算与异常Y值的辨别中。     

Characteristics of Deformation Layer for Vermicular Iron under Dry Sliding Friction

At room temperature, dry sliding wear tests were carried out using pin-on disc test rig, in which the pin is made of vermicular iron and the disc is made of 40Cr steel. The microstructures of the frictional surfaces for the pin specimens were investigated. Under the action ofboth frictional heat and frictional shearing stress, a plastic deformation layer under the frictional surface is formed. The morphology and properties of the plastic deformation layer depend on specimen material, contact pressure and frictional shearing stress. In the plastic deformation layer, the phosphorous mass percent varies at different depth and results in different hardness. On the outer side of surface, the hardness is the biggest and the phosphorous mass percent is the highest. They become gradually small from outer side to inner side of the surface.     

Tribotechnical characteristics of titanium diboride electrospark coatings

Conclusions The tribotechnical characteristics of an alloyed layer obtained by electroerosion hardening of 45 steel with TiB₂-Mo sintered materials were studied. It was established that at increased temperature the maximum wear resistance is possessed by a hardened layer in alloying with a material containing the optimum quantity of hard and plastic phases. A higher content of hard phase leads to brittle failure of the hardened layer and an increased content of plastic phase to seizing of the contacting pairs.Translated from Poroshkovaya Metallurgiya, No. 5(269), pp. 86–88, May, 1985.     

热轧不锈钢复合板力学性能及工艺优化

研究了热轧不锈钢复合板的力学性能及工艺优化。借助显微组织观察技术及热模拟技术对复合板复层塑性恶化的原因及不锈钢再结晶行为进行了研究,并结合研究结果,通过再热处理进行了工艺优化。结果表明,低温终轧使得复层产生明显的加工硬化是导致不锈钢复层塑性恶化的主要原因,通过适当温度的再热处理可以明显改善复层的塑性,获得理想的强塑性匹配。     

Effects of Ultrasonic Vibration on Material Flow and Thermal Cycles in Friction Stir Welding of Dissimilar Al/Mg Alloys

Comparative experiments are performed in friction stir welding (FSW) of dissimilar Al/Mg alloys with and without assistance of ultrasonic vibration. Metallographic characterization of the welds at transverse cross sections reveals that ultrasonic vibration induces differences in plastic material flow in two conditions. In FSW, the plastic material in the peripheral area of shoulder-affected zone (SAZ) tends to flow downward because of the weakening of the driving force of the shoulder, and a plastic material insulation layer is formed at the SAZ edge. When ultrasonic vibration is exerted, the stirred zone is divided into the inner and outer shear layers, the downward material flow trend of the inner shear layer disappears and tends to flow upward, and the onion-ring structure caused by the swirl motion is avoided in the pin-affected zone. By improving the flow behavior of plastic materials in the stirred zone, ultrasonic vibration reduces the heat generation, accelerates the heat dissipation in nugget zone and changes the thermal cycles, thus inhibiting the formation of intermetallic compound layers.

     

搅拌球磨过程中Ni-Ti粉末的组织变化与其塑性变形的关系

研究了Ni₅₀Ti₅₀单质混合粉末在不同工艺条件下球磨时层状组织的形成与变化,并根据球磨过程中粉末塑性变形模型研究了层片间距与球磨过程中粉末塑性变形的关系。     

The fracture resistance of a model metal/ceramic interface

Crack propagation has been measured for the Al₂O₃/Au interface subject to conditions that exclude stress corrosion. Crack growth has been shown to occur with a rising resistance, governed by intact metal ligaments in the crack wake. The level of resistance also increases as the metal layer thickness increases. Crack extension occurs by a combination of plastic void growth and interface debonding. The fracture energies are much larger than the work of adhesion, but appreciably smaller than those expected for ductile interface fracture. The fracture energy is nevertheless dominated by plastic dissipation, which increases at larger metal layer thicknesses.     

Microstructural Modification of Laser-Deposited High-Entropy CrFeCoNiMoWC Alloy by Friction Stir Processing: Nanograin Formation and Deformation Mechanism

Metallurgical and Materials Transactions A - Nanostructured CrFeCoNiMoWC high-entropy alloy layer was developed through laser-melting deposition and severe plastic deformation (SPD). The...     

Interaction of iron and aluminum in the plastic deformation and fast heating of laminar Fe–Al composite

The influence of plastic deformation and the heating rate on the solid-phase interaction of steel strip and aluminum powder is investigated. Recrystallization of the contacting materials determines the phase formation. The layer thickness of the Fe–Al intermetallides is plotted as function of the strain and heating rate. On that basis, the parameters of the transition layer may be predicted in selecting the technological conditions.     

Influence of plastic deformation upon the half-width of engineering metallic materials in hard state

The half-width values of the X-ray diffraction profiles are frequently used to characterize the static strength of a strengthened surface, or the depth distribution of this mechanical parameter, in a strengthened surface layer, especially in a shot-peening affected layer. However, for the unpeened surface and the base material of the shot-peened specimen of an alloy steel treated in hard state, the experimental results shown in this article indicate that uniaxial tensile or compressive plastic deformation increases the yield strengths while it decreases the half-width values. The half-width values of the shot-peened surface and surface layer greatly decrease, whereas the yield strength of this surface remarkably increases. Accordingly, in the authors’ opinion, the half-width values could not correctly describe the static strengths of hard metallic materials, and, contrary to the viewpoint put forward by a lot of researchers, the shot-peened surfaces of such materials are work hardened instead of work softened. A model demonstrating that plastic deformation reduces the half-width values by decreasing the second kind internal stresses is developed.     

塑管?混凝土界面密闭性能改善措施

为改善塑管混凝土结构的界面密闭性能,研究了在塑管?混凝土界面粘贴一种双面压敏胶带——Preprufe胶带的作用。通过界面黏结强度、界面渗水高度和界面透气性实验,测得塑管混凝土结构的界面黏结强度、界面渗水高度、气体压力?时间衰减曲线,推导出界面渗透指数。试验结果表明,界面黏结强度与粘贴胶带的宽度的关系可初步认为符合幂函数分布,压敏性粘合剂胶层与液态混凝土在硬化过程中形成的黏结强度远大于普通黏性层与塑管间的黏结强度。粘贴Preprufe胶带可显著提高塑管?混凝土界面抗渗能力。界面渗透指数随粘贴胶带的宽度增大呈明显的递减趋势,粘贴220 mm宽胶带的塑管混凝土试件界面渗透指数仅为基准塑管混凝土试件的2.86%。Preprufe双面压敏胶带在改善塑管?混凝土界面密闭性能上有良好的表现。在工程应用中可综合考虑所需效果和价格成本来选取粘贴胶带的宽度。