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利用阳极离子束技术在SKD11型不锈钢和YG6硬质合金上沉积类金刚石(DLC)薄膜,采用扫描电子显微镜、原子力显微镜、Raman光谱分析薄膜微观结构和表面形貌;采用WS-2005型附着力划痕仪和洛氏压力机测试膜基结合强度;采用球磨仪测试膜层耐磨性能。结果表明:利用该技术所制DLC膜是一种非晶结构、表面平整的薄膜,粗糙度R a值仅为5.21nm。DLC/Cr/SKD11膜系Raman光谱I D/I G值(0.69)高于DLC/Cr/YG6膜系(1.54),说明SKD11高于YG6所制膜层的sp3C键含量;DLC/Cr/SKD11膜系结合强度(17.8 N)低于DLC/Cr/YG6膜系(39.2 N),且DLC/Cr/YG6膜系的洛氏压痕周围仅有放射状微细裂纹,而DLC/Cr/SKD11膜系的压痕周围存在膜层脱落现象;沉积在SKD11与YG6基体上DLC膜的单位磨损率分别为1.40E-4和8.81E-5,说明YG6基体上DLC膜层的耐磨性要优于SKD11基体上的DLC膜层。由此看出,不同基体上制备的DLC膜层微观结构不同,导致结合性能及耐磨性能不同。 相似文献
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磁过滤真空弧源沉积C/C多层复合膜的结构和力学性能研究 总被引:2,自引:0,他引:2
采用磁过滤直流阴极真空弧源沉积技术在不锈钢基体表面制备了C/C多层复合膜,通过X射线光电子能谱、Raman光谱对薄膜的结构进行表征;C/C多层膜大气下的摩擦损性能在销盘式摩擦磨损试验机上进行;用洛氏压痕法研究了薄膜与基体的结合强度.结果表明:C/C多层复合膜为类金刚石结构.它与SiC球大气下的摩擦系数为0.10左右,其摩损性能由于多层膜的引入而显著提高.Ti过渡层的引入显著提高了膜基结合力. 相似文献
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为了研究W掺杂对类金刚石薄膜性能的影响,采用非平衡磁控溅射方法,通过改变WC靶功率,在YG6硬质合金基体上制备了5组不同W原子百分数(0%~14%)的含氢类金刚石薄膜(a-C:H:W)。用扫描电镜分析了薄膜的形貌,用拉曼光谱分析了薄膜的微观结构,分别用纳米压痕仪、划痕仪、摩擦磨损试验仪测试了薄膜的纳米硬度、膜基结合力和摩擦学性能。结果表明,a-C:H:W薄膜表面为丘状颗粒,随着WC靶功率的增加,颗粒尺寸先减小后增加;W掺杂可促进薄膜的石墨化;W原子百分数为4%的薄膜的临界划痕力Lc2值达到78.28 N,磨损率为5.8×10-8 mm3/(N·m),摩擦因数为0.09。 相似文献
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采用热丝化学气相沉积(HFCVD)技术在WC-Co8%硬质合金刀具表面制备金刚石涂层,调节甲烷浓度等沉积工艺制备了单层金刚石涂层刀具和微米金刚石涂层(1.2 μm)、纳米金刚石涂层(200 nm)交替多层金刚石涂层刀具。以7075航空铝合金作为切削工件,在无润滑干切条件下测试了单层金刚石涂层刀具和多层金刚石涂层刀具的切削性能。实验结果表明,切削2 h后单层金刚石涂层刀具涂层脱落宽度达到35 μm,刀刃钝化;有多层金刚石涂层刀具的刃型保持完整,涂层无脱落。对单层金刚石涂层和多层金刚石涂层平面样品进行了洛氏压痕实验。结果表明,多层金刚石涂层的脱落面积约为单层金刚石涂层脱落面积的1/5到1/10,进一步说明多层金刚石涂层有更强的抵抗裂纹产生的能力。这些结果表明,金刚石多层结构能提高涂层与基体的界面结合力,延长金刚石涂层刀具的使用寿命。 相似文献
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金刚石薄膜涂层硬质合金刀具的界面表征 总被引:3,自引:0,他引:3
采用SEM对金刚石薄膜涂层硬质合金刀具的金刚石薄膜表面、背面及金刚石薄膜剥落后的硬质合金刀片表面的典型形貌进行了观察,并采用TEM对金刚石薄膜/硬质合金刀片横截面的微观组织进行了研究,还采用FT—Raman光谱法对金刚石薄膜表面及金刚石薄膜剥落后的硬质合金刀片表面的微观结构进行了表征.结果表明:经适当的化学侵蚀脱钻和等离子体刻蚀脱碳预处理后,金刚石薄膜涂层硬质合金刀具的界面通常存在薄的(数十nm)石墨碳层;局部区域见到金刚石粒子直接生长在WC颗粒上,金刚石膜/基横截面的典型组织层次为:金刚石薄膜/薄的石墨碳层/细小的WC层/残留的脱碳层(η相+W相)/原始的硬质合金基体. 相似文献
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为了更高效地加工碳/碳复合材料,在硬质合金刀具上采用热丝CVD法(HFCVD)沉积了微米纳米复合金刚石(micro-nanocrystalline composite diamond, MNCD)薄膜,即先在基体表面沉积一层微米金刚石(microcrystalline diamond, MCD)薄膜,然后不间断地原位沉积一层纳米金刚石(nanocrystalline diamond, NCD)薄膜。通过扫描电子显微镜和拉曼光谱仪对MNCD薄膜的形貌和质量进行表征,利用切削试验研究了MCD涂层刀具、MNCD涂层刀具和硬质合金刀具的切削性能。结果表明:涂覆的MNCD薄膜质量很高,横断面上微米金刚石颗粒以柱状晶的方式生长,纳米金刚石颗粒以堆叠的方式生长,两者之间有明显的界限;切削试验中,MNCD涂层刀具由于具有MCD薄膜的膜基结合力好的优点,同时又兼有NCD薄膜表面摩擦系数小的优点,在3种刀具中表现良好;可以看出,MNCD薄膜可极大地提升工具的切削性能,延长刀具的使用寿命。 相似文献
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钢渗铬层上金刚石薄膜的表面、界面结构及附着性 总被引:1,自引:0,他引:1
在钢渗铬层表面用化学气相沉积(CVD))法制备了金刚石薄膜.使用扫描电镜(SEM)、透射电镜(TEM)和压痕法研究了金刚石膜的表面、界面结构及附着力.用拉曼光谱分析了金刚石膜的纯度及非金刚石碳相.甲烷含量超过0.6%(体积分数)后,金刚石膜为球形纳米晶,形核密度>107cm-2.用甲烷含量为0.6%(体积分数)沉积的金刚石膜表面的残余压应力为1.22 Gpa,而膜背面的残余压应力更高,达2.61 Gpa.压痕显示在19.6 N载荷下膜发生开裂.TEM观察发现,膜/基界面为微观非平面,有利于提高金刚石膜的附着力. 相似文献
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研究了镀锡钢板在镀锡状态下和去除镀锡层后的硬度变化情况。应用统计方法对实验数据进行了分析。结果表明,镀锡状态下的硬度Xi与去除锡层后的硬度Yi之间存在如下关系;Yi=1.774+0.997Xi。分析了产生这种现象的原因,认为主要与使用的试台有关。 相似文献
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J. F. Song F. F. Rudder Jr. T. V. Vorburger J. H. Smith 《Journal of research of the National Institute of Standards and Technology》1995,100(5):543-561
National and international comparisons in Rockwell hardness tests show significant differences. Uncertainties in the geometry of the Rockwell diamond indenters are largely responsible for these differences. By using a stylus instrument, with a series of calibration and check standards, and calibration and uncertainty calculation procedures, we have calibrated the microform geometric parameters of Rockwell diamond indenters. These calibrations are traceable to fundamental standards. The expanded uncertainties (95 % level of confidence) are ±0.3 μm for the least-squares radius; ±0.01° for the cone angle; and ±0.025° for the holder axis alignment calibrations. Under ISO and NIST guidelines for expressing measurement uncertainties, the calibration and uncertainty calculation procedure, error sources, and uncertainty components are described, and the expanded uncertainties are calculated. The instrumentation and calibration procedure also allows the measurement of profile deviation from the least-squares radius and cone flank straightness. The surface roughness and the shape of the spherical tip of the diamond indenter can also be explored and quantified. Our calibration approach makes it possible to quantify the uncertainty, uniformity, and reproducibility of Rockwell diamond indenter microform geometry, as well as to unify the Rockwell hardness standards, through fundamental measurements rather than by performance comparisons. 相似文献
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V. R. Howes 《Journal of Materials Science》1991,26(1):75-81
A Rockwell superficial hardness tester has been used to continuously monitor hardness under load with time. An analysis of the Rockwell test, that showed the relationship between the measured parameters and the on-load hardness and elastic recovery has been quantitatively verified.Low homologous temperature, high stress, indentation creep in the macrohardness range has been measured for aluminium, copper and mild steel, but was not detectable for brass and silver steel. The stress relaxation was no more than 10% and appeared to follow an exponential decay to an equilibrium value. The difference between normal uniform tensile creep and indentation creep, and explanations for the latter, have been discussed, and the measured relaxation time has been related to a ratio of elastic and creep indentation material constants.Bearing in mind the world-wide availability of Rockwell hardness testers, it is suggested that this extension to creep testing, and possibly fatigue testing, may be a useful development for industrial non-destructive quality control and specification checking of materials and components. 相似文献
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Li Ma Jack Zhou Alan Lau Samuel Low Roland deWit 《Journal of research of the National Institute of Standards and Technology》2002,107(5):401-412
The indentation process of pressing a Rockwell diamond indenter into inelastic material has been studied to provide a means for the analysis, simulation and prediction of Rockwell hardness tests. The geometrical characteristics of the spheroconical-shaped Rockwell indenter are discussed and fit to a general function in a self-similar way. The complicated moving boundary problem in Rockwell hardness tests is simplified to an intermediate stationary one for a flat die indenter using principle of similarity and cumulative superposition approach. This method is applied to both strain hardening and strain rate dependent materials. The effects of different material properties and indenter geometries on the indentation depth are discussed. 相似文献
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李晓东 《理化检验(物理分册)》2010,(4):274-276
通过试验阐述了影响洛氏硬度试验结果的主要因素以及洛氏硬度测试时应注意的问题。结果表明:试样表面粗糙度、试样平行度以及试样厚度等因素都会对试验结果产生影响;在洛氏硬度测试时应注意硬度计的检验、试验力的保持时间,试样表面粗糙度以压痕位置等问题。 相似文献
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依据GB/T230.1—2009规定的试验方法,利用Wilson 2001T洛氏硬度计对某钢厂X70管线钢进行了洛氏硬度(HRB)试验,从试验重复性、硬度计复现性等多方面对洛氏硬度试验的不确定度来源进行了分析和阐述,对每个不确定度分量进行了逐一评定,最终给出了扩展不确定度及测量结果的不确定度报告。结果表明:该X70管线钢洛氏硬度测量平均值为(78.5±2.4)HRB,包含因子k=2。该方法对金属材料洛氏硬度的测量不确定度评定具有一定的参考价值。 相似文献
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硬度测试技术的新动态与发展趋势 总被引:6,自引:0,他引:6
虞伟良 《理化检验(物理分册)》2003,39(8):401-405,435
对目前国际上硬度测试技术的最新发展与趋势进行了分析研究,简要介绍了宏洛氏硬度、超微压痕硬度及世界统一的洛氏硬度标尺等试验方法,并对今后硬度测试技术的发展和趋势进行了预测。 相似文献
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研究了淬回火GCr15钢洛氏硬度与马氏体(211)晶面X射线半高宽间的关系,用数理统计方法对实验数据进行了分析。结果表明,洛氏硬度与半高宽间存在良好的相关性,相关系数约为0.973;建立了洛氏硬度与半高宽间的线性均方回归方程,利用该方程可预测淬回火GCr15钢的硬度。 相似文献