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1.
基体温度对Ti6Al4V表面渗Mo合金层性能的影响   总被引:5,自引:0,他引:5  
利用双层辉光离子渗金属技术在Ti6A14V表面渗Mo,形成了表面改性合金层,就910—990℃渗Mo时基体温度对表面合金层性能的影响进行了研究。结果表明,渗Mo后的表面合金层由扩散层和沉积层组成,沉积层呈(211)晶面的择优取向。随着基体温度的升高,扩散层的厚度增加,并且合金层表面粗糙度增大。渗Mo后的表面合金层硬度较基体Ti6A14V的大大提高,而基体温度变化对合金层硬度没有明显影响。用涂层压入仪对沉积层和扩散层间的结合强度进行了评定。研究表明,随着基体温度的升高,临界压入载荷Pc增大,沉积层和扩散层间的结合强度增大。  相似文献   

2.
Ti6Al4V无氢离子渗氮摩擦学性能的研究   总被引:3,自引:0,他引:3  
以N2和Ar的混合气为气源,在Ti6Al4V表面离子渗氮形成渗氮层。对渗层的相结构、表面粗糙度、显微硬度及与基体的结合强度等进行了测试分析,并用球-盘滑动磨损试验机对渗层的摩擦学性能进行了研究。结果表明:在N2/Ar=1:1,900℃的渗氮条件下,渗氮层主要由化合物Ti2N,TiN和氮在α-Ti中的固溶体α相等相组成;渗氮后试样的表面粗糙度增大;渗氮层的硬度较基材Ti6Al4V有很大提高,且与基体间有较好的结合强度;在球-盘滑动磨损试验中,渗氮层无减摩效果,但其耐磨性较基材Ti6Al4V大大增强。  相似文献   

3.
静电纺丝制备连续SiC亚微米/纳米纤维   总被引:1,自引:0,他引:1       下载免费PDF全文
采用镶嵌靶反应磁控溅射技术,通过调节氮分压及基体偏压在M2高速钢基体表面制备了一系列耐热的(Ti,Al)N硬质薄膜,并用XRD,EDS及纳米压入法、划痕法等方法研究了(Ti,Al)N薄膜的成分、相结构与力学性能的关系。结果表明,氮分压和基体偏压对(Ti,Al)N薄膜取向及Ti、Al、N原子含量有明显影响,从而导致薄膜硬度及膜基结合性能发生变化。研究中,在氮分压为33.3×10-3Pa、基体偏压为-100V时制备的(Ti,Al)N薄膜力学性能最优,其纳米硬度为43.4GPa,达到40GPa超硬薄膜的要求。  相似文献   

4.
以钛和石墨为原料,采用预置粉末结合高频感应加热熔化的方法在Ti6Al4V基体表面制备了原位自生TiC增强Ti基复合涂层,研究了涂层微观结构、物相构成、纳米力学性能及显微硬度。结果表明,感应熔覆钛基复合涂层表面平整,内部无裂纹和孔隙,与基体形成了冶金结合;熔覆过程中Ti与石墨充分反应生成TiC增强相,涂层基质相由α-Ti和少量β-Ti构成;TiC在涂层内分布均匀,其纳米压痕硬度和弹性模量高达22和280 GPa,较Ti6Al4V基体分别提高18和130 GPa,因此使复合涂层具有较高的硬度。  相似文献   

5.
采用磁控溅射方法在Ti6Al4V钛合金表面制备纳米晶TiN梯度涂层,研究涂层的显微组织和力学性能,并对涂层和Ti6Al4V合金基体在生理环境中的电化学腐蚀行为和腐蚀磨损性能进行比较。结果表明:纳米晶TiN的梯度分布有利于释放涂层中的内应力,使粘附强度增加到90 N。致密的结构和细化的晶粒使涂层表面纳米硬度达到28.5 GPa,纳米晶TiN涂层的防腐蚀效率达到96.6%。与Ti6Al4V合金基体相比,纳米晶TiN涂层的耐腐蚀磨损性能提高了100倍。纳米晶TiN梯度涂层具有良好的化学稳定性和较高的H~3/E~2比(H为硬度,E为弹性模量),是改善耐腐蚀性能和抗磨损性能的主要原因。  相似文献   

6.
采用磁控溅射技术在PCr Ni3Mo钢表面沉积Cr Al N硬质涂层,利用激光共聚焦显微镜、X射线衍射仪、纳米压痕仪分别对涂层的表面形貌、组织结构、硬度与弹性模量进行表征。结果表明,Cr Al N涂层表面较致密光滑,表面粗糙度为0.003 5μm。Cr Al N涂层的硬度和弹性模量分别为14.03 GPa和259.1 GPa,较基材显著提高。  相似文献   

7.
高速钢表面多弧离子镀(Ti,Al)N薄膜及性能研究   总被引:2,自引:1,他引:2  
金犁  潘应君 《热加工工艺》2006,35(16):59-61
采用多弧离子镀技术在W18Cr4V表面制备出(Ti,Al)N硬质薄膜,研究了Al含量对(Ti,Al)N薄膜的形貌、硬度、膜基结合力、耐磨性、摩擦系数的影响。并利用扫描电镜、X射线衍射仪对薄膜进行了分析。结果表明Al含量在25%左右的(Ti,Al)N薄膜硬度达到2780HV0.05,耐磨性好,摩擦系数仅为0.168,且与钢基体结合良好.具有最佳的综合性能。  相似文献   

8.
钛合金表面微弧氧化膜的特点及成膜分析   总被引:23,自引:0,他引:23  
用微弧氧化方法在钛合金上形成二氧化钛薄膜,用扫描电镜、X射线衍射以及透射电镜分析了膜的组织结构和化学成分,用纳米压入仪和划擦仪测量了膜的硬度和弹性模量及划擦抗力。结果表明,钛合金表面形成一层微弧氧化膜,含有纳米晶结构。薄膜由晶体和少量非晶体组成,硬度和弹性模量分别为0.78GPa和35.6GPa,划擦过程中未出现膜从基体表面的剥落,但高载荷下膜本身有破坏和脱落。  相似文献   

9.
钛合金圆环工件表面合金化及其滚动摩擦性能研究   总被引:1,自引:1,他引:0  
采用等离子表面合金化技术在Ti6Al4V合金圆环工件表面制备Mo渗镀改性层,将其与未渗Mo处理的Ti6Al4V合金在模拟实际工况条件下进行油润滑的滚动摩擦对比试验,比较二者的磨损情况,并分析磨损机理。结果表明,Ti6Al4V合金表面进行渗Mo处理后,形成了均匀、致密且高硬度的Mo基改性层。Ti6Al4V合金表面渗Mo后,硬度由渗层到基体呈梯度分布。滚动摩擦试验表明,渗Mo处理后表面无减摩效果,但磨损量大大减小,耐磨性得到有效改进。通过对磨损形貌的分析可知,表面渗Mo处理后磨损机理主要以磨粒磨损为主,而基材是磨粒磨损和粘着磨损。  相似文献   

10.
采用磁控溅射技术在PCrNi3Mo钢表面沉积了CrN涂层。利用激光共聚焦显微镜、扫描电镜(SEM)、纳米压痕仪、X射线衍射仪(XRD)对涂层的形貌、硬度与弹性模量和相结构进行了表征,研究了基体负偏压、溅射电流和N2/Ar流量比对溅射涂层结构和力学性能的影响。结果表明:在基体负偏压为100 V、溅射电流为0.2 A、N2/Ar流量比为1时溅射的CrN涂层质量最佳,其硬度和弹性模量分别为21.38 GPa和272.71 GPa,较PCrNi3Mo钢基体的硬度(5.57 GPa)与弹性模量(258 GPa)明显提高。  相似文献   

11.
吴玉梅  熊晓云  靳蓉  孙敬民  杨林  罗晓星 《金属学报》2005,10(10):1100-1103
目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。  相似文献   

12.
Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.  相似文献   

13.
The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.  相似文献   

14.
《中国铸造》2014,(6):537-538
The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.  相似文献   

15.
《中国铸造》2014,(6):542-546
China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society (FICMES) each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.  相似文献   

16.
正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.  相似文献   

17.
正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis  相似文献   

18.
Preface     
<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of  相似文献   

19.
The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.  相似文献   

20.
The development of computer controlled continuous rolling process calls for a mathematical expression that can express the inequality condition of "constant flow". Tension is the link of the continuous rolling process. From the condition of dynamic equilibrium, a differential equation of tension is given out. On the basis of the physical rules established from the industrial practice and experimental studies, the law of volume constancy, the linear relation of forward slip and tension, the state equation of continuous rolling, the formula of dynamic tension, and the formula of static tension have been obtained. These formulae reflect the functional relations between tensions, thickness, roll velocity, and time in the continuous rolling process. It is implied that the continuous rolling process is a gradually steady, controllable, and measurable dynamic system. An assumption of predicting the thickness of a steel plate using these tension formulae is also put forward.  相似文献   

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