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轧辊激光毛化技术的用途是什么? 什么样的轧辊需要毛化处理? 激光毛化轧辊技术
的优势是什么? 还存在什么不足? 激光毛化处理为什么能够延长轧辊的寿命? 激光毛化轧辊
改善了所轧钢板的哪些性能? 其机制是什么? 针对轧辊激光毛化技术的这几个基本问题
进行了讨论和释疑, 并指出了下一步的改进方向. 相似文献
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半穿甲弹设计及穿甲实验研究 总被引:1,自引:0,他引:1
为提高半穿甲弹的穿甲能力,设计了一种贫铀半穿甲实验弹。对实验弹的飞行稳定性进行了理论分析及数值模拟,两种方法计算得到的实验弹稳定储备量基本吻合,且能够满足实验弹的飞行稳定性要求。采用100mm滑膛炮,开展了贫铀半穿甲弹侵彻装甲靶板实验。实验结果表明,实验弹飞行稳定,与理论分析及数值模拟结果一致;实验弹在25°倾角下贯穿三层20mm厚GY4装甲钢,且回收到的弹体基本完好。通过对实验后的实验弹和靶板进行分析,认为贫铀半穿甲弹的穿甲能力较强。 相似文献
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激光硬化9SiCr表面土壤磨损研究 总被引:6,自引:0,他引:6
在壤土、沙土和黏土3种土壤中对激光处理的9SiCr材料进行磨损试验,考察了激光硬化工艺参数对9SiCr 旋耕刀基体显微硬度的影响,获得9SiCr 旋耕刀基体激光硬化处理的最佳工艺参数。结果表明:在激光功率为1 200W、扫描速度为14mm/s和激光功率1500W、扫描速度16mm/s的条件下,磨损率较小。激光处理表面在3种土壤条件下进行了耐磨性比较,沙土对试件的磨损率影响最小。9SiCr经过激光处理其表面耐磨性比一般淬火表面的耐磨性提高约5倍。9SiCr表面磨损形式主要是磨粒磨损。激光处理9SiCr表面提高了表面硬化层的硬度,从而提高了材料的耐磨性,增加了9SiCr的使用寿命。 相似文献
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Wear-resistant coatings were prepared on the surface of the Q235 low-carbon steel plate by HVAS with the carbonitride alloying self-shielded flux-cored wire. Detection and analysis on the microstructure and properties of the coatings were carried out by using scanning electron microscope, microhardness tester and wear tester. The forming, the wear resistance and its mechanism of the coatings were studied. The results show that the coatings have good forming, homogeneous microstructure and compact structure. The coatings have good hardness, the average microhardness value reaches 520 HV0.1, and the highest value is up to about 560 HV0.1. As a result, the coatings have good abrasive wear performance and adhesion strength. 相似文献
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Pengfei Chui Kangning Sun Chang Sun Xiuqing Yang Ting Shan 《Applied Surface Science》2011,257(15):6787-6791
A nanostructured layer was fabricated by using fast multiple rotation rolling (FMRR) on the surface of 316L stainless steel. The microstructure in the surface was characterized by transmission electron microscopy and X-ray diffraction. The effects of FMRR on the microhardness, surface roughness and corrosion behavior of the stainless steel were investigated by microhardness measurements, surface roughness measurements, potentiodynamic polarization curves and pitting corrosion tests. The surface morphologies of pitting corrosion specimens were characterized by scanning electron microscopy. The results show that FMRR can cause surface nanocrystallization with the grain size ranges from 6 to 24 nm in the top surface layer of the sample. The microhardness of FMRR specimen in the top surface layer remarkably increases from 190 to 530 HV. However, the surface roughness slightly rises after FMRR treatment. The potentiodynamic polarization curves and pitting corrosion tests indicated that the FMRR treated 316L stainless steel with a surface nanocrystallized layer reduced the corrosion resistance in a 3.5% NaCl solution and enhanced the pitting corrosion rate in a FeCl3 solution. Possible reasons leading to the decrease in corrosion resistance were discussed. 相似文献
100.
Peter Jur?i 《Applied Surface Science》2011,257(24):10581-10589
Samples made from Vanadis 6 PM ledeburitic tool steel were surface machined, ground, and mirror polished. They were heat treated and coated with CrN with and without Ag addition by reactive magnetron sputtering. The CrN film grew in a typically columnar manner. A small addition of 3% Ag did not lead to alterations in the growth mechanism. The hardness of the CrN coating was 16.79 ± 1.49 GPa compared to 15.97 ± 1.44 GPa for the coating with Ag addition. The Ag addition in the CrN improved adhesion of the coating, which can be attributed to the capability of CrAgN coating to accommodate higher deformation energy before failure. The CrAgN coating exhibited superior tribological properties at intermediate temperatures. Compared to pure CrN the friction coefficient is lowered to 70-75% when measured at 400 and 500 °C, respectively. This is reflected in a reduction in the volume wear, which was found to be three times lower for the coating containing Ag. Flexural strength decreased slightly for the CrN- or CrAgN-coated material compared to uncoated steel. However, as the decrease in flexural strength is very weak there is practically no risk of significant embrittlement of the investigated material due to the CrN coating with or without Ag addition. 相似文献