共查询到19条相似文献,搜索用时 179 毫秒
1.
强流脉冲电子束表面改性30SiMn2MoVA钢的耐磨性能 总被引:1,自引:1,他引:0
目的提高30SiMn2MoVA钢表面的耐磨性。方法通过强流脉冲电子束技术,对30SiMn2MoVA钢表面进行不同脉冲次数的轰击处理,分析表面改性前后试样的硬度及摩擦磨损性能。结果强流脉冲电子束处理30SiMn2MoVA钢表面晶粒细化,产生宏观残余应力使表面硬度提高。30次脉冲处理后,硬度达到最大值,相比于原始试样提高了39.6%。材料的磨损量随脉冲次数的增加而降低,表面耐磨性比原始试样提高了1倍左右,其中30次脉冲处理后,耐磨性提高最大。结论通过强流脉冲电子束技术,提高了30SiMn2MoVA钢表面的耐磨性。 相似文献
2.
3.
激光淬火基体对镀铬层断裂韧性的影响 总被引:3,自引:0,他引:3
为提高30CrNi2MoVA钢镀铬身管的寿命,采用YAG激光器对钢基体进行激光搭接淬火再镀铬的复合工艺.用多裂纹拉伸技术对经激光搭接处理的30CrNi2MoVA钢再镀铬后的铬层和普通铬层的断裂韧性进行比较.结果表明,激光淬火处理基体可以提高镀铬层的断裂韧性.力学模型分析表明,基体残余压应力以抵抗基体拉伸变形的方式提高了铬层的断裂韧性;化学去基体法研究铬层界面表明,激光处理基体以细化基体影响层的晶粒形式提高了铬层的强度和韧性.离子刻蚀横截面对拉伸结果作了进一步验证. 相似文献
4.
针对渗氮性能、热稳定性及淬透性要求,在33CrMoV12-9和40CrMoV13-9钢基础上调整化学成分,并借助JmatPro软件探究其热强性,设计了BTHJ渗氮钢。晶粒度、端淬试验以及与38CrMoAl钢对比进行的渗氮和热稳定性试验表明:920 ℃奥氏体化后BTHJ钢的晶粒度为10级,淬透深度可达80 mm;调质后经550 ℃保温60 h,硬度维持在40 HRC以上,具有较好的热稳定性;气体渗氮后表面硬度1017 HV0.2,渗氮层硬度梯度平缓,无脉状组织,渗氮性能良好,各项性能均优于38CrMoAl钢。 相似文献
5.
6.
7.
8.
30Cr2MoV钢离子渗氮工艺的改进 总被引:2,自引:0,他引:2
本文对 30Cr2MoV钢进行了变温离子渗氮和普通离子渗氮两种工艺处理 ,借助显微硬度计和X射线衍射仪进行了分析。结果表明 :变温离子渗氮后获得的表面硬度和渗氮层性能明显优于普通离子渗氮者 相似文献
9.
10.
11.
12.
G. I. Cubillos J. J. Olaya M. Bethencourt G. Cifredo G. Blanco 《Journal of Thermal Spray Technology》2013,22(7):1242-1252
Coatings of zirconium oxide were deposited onto three types of stainless steel, AISI 316L, 2205, and tool steel AISI D2, using the ultrasonic spray pyrolysis method. The effect of the flux ratio on the process and its influence on the structure and morphology of the coatings were investigated. The coatings obtained, 600 nm thick, were characterized using x-ray diffraction, scanning electron microscopy, confocal microscopy, and atomic force microscopy. The resistance to corrosion of the coatings deposited over steel (not nitrided) and stainless steel nitrided (for 2 h at 823 K) in an ammonia atmosphere was evaluated. The zirconia coating enhances the stainless steel’s resistance to corrosion, with the greatest increase in corrosion resistance being observed for tool steel. When the deposition is performed on previously nitrided stainless steel, the morphology of the surface improves and the coating is more homogeneous, which leads to an improved corrosion resistance. 相似文献
13.
14.
J. Hardell B. Prakash 《International Journal of Refractory Metals and Hard Materials》2010,28(1):106-114
Tribological components operating at elevated temperatures can experience high wear, oxidation, thermal fatigue and changes in mechanical properties. In this work, the friction and wear characteristics of plasma nitrided and surface coated (CrN and TiAlN) tool steel during sliding against AISI52100 bearing steel have been studied at room temperature and 400 °C respectively using a ball on disc machine. Surface profiler and SEM/EDS techniques were used to characterise the surface topography and resulting surface damage of the test specimens. The results show that the friction of plasma nitrided tool steel during sliding against bearing steel ball is very high at room temperature and it drastically drops at 400 °C. The wear is mainly abrasive at room temperature and adhesive at elevated temperatures. In case of CrN coated tool steel the friction is high but its wear is negligible at room temperature. At 400 °C, the friction decreases marginally and transfer of bearing steel to the coated CrN coated disc has been observed. The TiAlN coating has shown relatively lower friction, compared to CrN and negligible wear at room temperature. At 400 °C, the friction is very high and unstable and transfer of TiAlN coating to the mating ball occurs. 相似文献
15.
为了提高TC4钛合金表面硬度和耐磨性能,通过等离子渗氮技术和多弧离子镀技术相结合的方法对TC4钛合金进行表面改性处理。通过扫描电镜、维氏显微硬度计、三维轮廓仪、高速往复摩擦磨损试验仪和电化学工作站,对比研究了TC4钛合金、渗氮层和CrAlSiN涂层的显微组织、硬度、耐磨性能和耐腐蚀性能。结果表明,经渗氮处理后,TC4合金表面渗氮层硬度提高了约2倍,在此基础上制备的CrAlSiN涂层的平均硬度高达3222 HV0.025,涂层表面存在少许大颗粒和凹坑;CrAlSiN涂层平均摩擦因数为0.22,磨损机理主要为粘着磨损,对磨副的材料粘着到涂层表面,而涂层几乎无磨损,耐磨性能显著提高。CrAlSiN涂层的自腐蚀电位为-0.542 V,比TC4钛合金基体的自腐蚀电位-0.747 V正移了0.205 V,表明在渗氮层基础上沉积CrAlSiN涂层显著提高了合金的耐电化学腐蚀性能。 相似文献
16.
《International Heat Treatment & Surface Engineering》2013,7(4):175-179
AbstractThe application of surface treatment methods like ion nitriding, physical vapour deposition (PVD) coatings and their combination in duplex treatments effectively reduces the occurrence of oxidation, corrosion, erosion and wear processes. However, it is still uncertain whether nitriding and duplex treatment have any real effect on the decrease in the nucleation and growth of thermal fatigue cracks on the surface. This paper presents the results of thermal fatigue investigations of a nitrided layer and different composite layers ‘nitrided layer/PVD coating’ (TiN, CrN and TiAlN) obtained on the EN X40CrMoV5·1 hot working steel. The ion nitrided only and three different duplex treated substrates were compared, based on the intensity of the thermal fatigue cracks observed after testing. The nitrided layer and composite layers investigated were obtained with the use of the hybrid surface treatment technology consisting of ion nitriding followed by arc evaporation coating deposition. Apparatus based on high frequency induction heating and water spray cooling was used for thermal fatigue tests under the following conditions: maximum temperature 600°C, minimum temperature 80°C and two different rates of thermal cycling: 500 and 1000. The thermal fatigue intensities of the nitrided layer and the three different composite layers were measured according to the surface crack density and crack length (i.e. penetration into the testpiece) after different numbers of thermal cycles. Finally, based on the results obtained, the influence of different PVD coatings in the composite layer on the increase in thermal fatigue resistance of hot working steel was discussed. 相似文献
17.
The influence of low temperature plasma nitriding on the wear and corrosion resistance of AISI 420 martensitic stainless steel was investigated. Plasma nitriding experiments were carried out with DC-pulsed plasma in 25% N2 + 75% H2 atmosphere at 350 °C, 450 °C and 550 °C for 15 h. The composition, microstructure and hardness of the nitrided samples were examined. The wear resistances of plasma nitrided samples were determined with a ball-on-disc wear tester. The corrosion behaviors of plasma nitrided AISI420 stainless steel were evaluated using anodic polarization tests and salt fog spray tests in the simulated industrial environment.The results show that plasma nitriding produces a relatively thick nitrided layer consisting of a compound layer and an adjacent nitrogen diffusion layer on the AISI 420 stainless steel surface. Plasma nitriding not only increases the surface hardness but also improves the wear resistance of the martensitic stainless steel. Furthermore, the anti-wear property of the steel nitrided at 350 °C is much more excellent than that at 550 °C. In addition, the corrosion resistance of AISI420 martensitic stainless steel is considerably improved by 350 °C low temperature plasma nitriding. The improved corrosion resistance is considered to be related to the combined effect of the solid solution of Cr and the high chemical stable phases of ?-Fe3N and αN formed on the martensitic stainless steel surface during 350 °C low temperature plasma nitriding. However, plasma nitriding carried out at 450 °C or 550 °C reduces the corrosion resistance of samples, because of the formation of CrN and leading to the depletion of Cr in the solid solution phase of the nitrided layer. 相似文献
18.
为了提高旋振筛机在筛分锂能电池的正、负极材料时的使用寿命和物料的纯洁度,研究了304不锈钢试块在520 ℃下离子渗氮时间对其组织、硬度和耐蚀性能的影响。利用维氏显微硬度计和光学显微镜对渗氮层进行了硬度和深度测试,用球盘式旋转摩擦磨损试验机对渗氮层进行了摩擦磨损性能测试,用电化学工作站进行了耐蚀性能测试,并用X射线衍射仪对试样渗层进行了物相分析。结果表明,相比未经渗氮处理,304不锈钢试块经过渗氮处理后,渗层30 μm深度处的硬度提高了5~6倍,渗层相对耐磨性为未经处理的24.5倍;尽管耐盐蚀性能降低,但其耐碱蚀性能提高。考虑到锂能电池的正极材料偏碱性和负极材料中性特点,旋振筛机上的304不锈钢网架和筛框经过离子渗氮处理后既可以大大提高旋振筛机的使用寿命,还能提高所筛分物料的纯洁度。 相似文献
19.
Plasma nitriding is a promising posttreatment technique to create a nitride layer on electroplated chromium coatings for improving their corrosion resistance. In the present study, the effects of plasma nitriding on the corrosion properties of electroplated chromium/C45 mild steel were investigated using electrochemical characterization. The chromium plated samples were nitrided using a pulsed direct current glow discharge in an NH3 atmosphere. The polarization curve measurement results showed that the plasma nitrided samples exhibited more positive corrosion potentials (Ecorr), smaller corrosion currents (Icorr), and evident passivation when compared with unnitrided chromium plating/substrate system. The high value of Ecorr and low value of Icorr imply an improvement of the corrosion resistance of the coating/substrate system after plasma nitriding. 相似文献