(Ti,Al,Zr)N多元硬质膜的退除方法与工艺研究

利用多弧离子镀技术并使用Ti-Al(原子百分比50∶50)合金靶与Zr单质靶组合在高速钢基体上镀覆(Ti,Al,Zx)N硬质反应膜.使用螯合剂、氧化剂、缓蚀剂及氢氧化钠配制膜层退除液,通过改变退除液各组元的浓度、退除液PH值和退膜温度等影响因素,考查(Ti,Al,Zr)N硬质反应膜的退除效果.分析了高速钢基体和退膜前后试样的表面形貌、成分和粗糙度.比较了退除液组元的不同组合、不同浓度、退除液不同PH值条件下镀膜试样表面形貌随时间的变化,进而确定了退除液的最佳组元组合及最佳退除膜层工艺,实现了高速钢基体上(Ti,Al,ZOr)膜的完全退除,退膜后的试样表面光亮,无腐蚀损伤.     

多弧离子镀(Ti,Al,Zr)N多元超硬梯度膜的制备及力学性能研究

采用多弧离子镀技术并使用合金靶Ti-Al-Zr制备(Ti,Al,Zr)N多元超硬梯度膜。利用扫描电镜、X衍射仪对(Ti,Al,Zr)N膜层表面、断面形貌、成分、结构进行观察测定;系统考察了沉积工艺对(Ti,Al,Zr)N膜层质量、膜/基附着力和硬度的影响;并对膜层抗热震性进行了研究。通过与TiN,(Ti,Al)N,(Ti,Zr)N等硬质膜进行比较,发现采用Ti-Al-Zr合金靶制备的(Ti,Al,Zr)N多元梯度膜有更高的硬度和膜/基附着力,硬度可达4000 HV,实现了从硬质膜到超硬膜的转变;膜/基附着力大于200 N,同时对沉积工艺有较强的适应性。     

多弧离子镀(Cr,Ti,Al,Zr)N多组元超硬梯度膜的结构及性能

(Cr,Ti,Al,Zr)N梯度膜性能优异。采用多弧离子镀技术,使用Ti-Al-Zr合金靶和Cr单质靶在高速钢表面制备(Cr,Ti,Al,Zr)N多元超硬梯度膜,利用扫描电镜、能谱、X射线衍射仪、硬度计、划痕仪对膜层形貌、成分、结构、硬度、附着力进行分析,并通过热震性能试验考察了膜层的抗热震性能。结果表明:制备的膜层为面心立方结构,择优生长取向为(220)面;与TiN,(Ti,Al)N,(Ti,Cr)N,(Ti,Al,Zr)N等硬质膜相比,制备的(Cr,Ti,Al,Zr)N多元梯度膜具有更高的硬度和膜/基附着力,硬度可达4400HV,膜/基附着力大于200N,实现了从硬质膜到超硬膜的转变;膜层中N含量梯度可有效减少应力集中,Cr,Al含量的增加有利于提高膜层抗热震性能;负偏压对膜层硬度影响较大,对膜层成分、结构、抗热震性能影响较小,对膜/基附着力基本无影响。     

(Ti,Al,Zr)N多元氮梯度硬质反应膜的组织结构和性能

采用多弧离子镀技术和Ti-Al合金靶及Zr单质靶的组合,在高速钢基体上制备了(Ti,Al,Zr)N多元N梯度硬质反应膜.分别用扫描电镜、X射线衍射仪观察测定(Ti,Al,Zr)N梯度膜膜层的表面、断面形貌、成分以及相结构,研究了(Ti,Al,Zr)N多元氮梯度硬质反应膜的组织结构和性能.结果表明,与TiN、(Ti,Al...     

真空管道TiN膜热出气率实验研究

简要叙述了小孔流量法测量材料出气率实验的原理和实验装置，给出了不锈钢溅射镀TiN膜在不同情况下的热出气率，并对影响不锈钢溅射镀TiN膜热出气率情况的各种因素进行了分析，为使用溅射镀TiN膜表面处理的储存环真空室的设计提供了依据。     

PVD法制备的(Ti,Al)N硬质膜热稳定性研究

采用空心阴极离子束辅助多弧离子镀技术在高速钢表面沉积(Ti,Al)N硬质膜,并将其分别在空气和保护气氛中、不同温度下加热,研究膜层的热稳定性。利用X射线衍射和差热分析方法确定了相组成及其变化;观察和检测了膜的表面形貌、粗糙度和纳米压痕硬度。结果表明,膜表面粗糙度0.2190,硬度值34.19 GPa,经空气中700℃加热后,膜层中TiN相开始分解生成TiO_2,当温度升至900℃时膜分解开裂,硬度值降至12.27 GPa,失去保护作用。而在保护气氛下,膜层经1200℃高温加热后与未加热膜相比较,物相组成与表面形貌稍有变化,硬度值降为28.23 GPa。显示出(Ti,Al)N膜具有良好的热稳定性。     

(Ti,Al, Cr)N膜系的研究进展

总结了(Ti,Al,Cr)N膜系的沉积方法并讨论了化学成分、N2流量以及基底偏压等工艺参数对薄膜产生的影响,针对(Ti,Al,Cr)N膜系的相组成与膜层成分、抗氧化性、耐腐蚀性、显微硬度、抗摩擦磨损性能以及膜基结合力等方面进行了详细阐述.在此基础上,对(Ti,Al,Cr)N膜系的未来发展进行了展望,以期为多组元氮化物硬质膜的研究提供参考.     

中间层类型对类金刚石涂层键合结构和性能的影响行为

采用阴极电弧离子镀和等离子体增强化学气相沉积(PECVD)相结合的技术方法,在304不锈钢基体上分别沉积制备了Ti/DLC和Ti/Ti N/Ti Al N/DLC复合涂层。选用原子力显微镜、拉曼光谱对涂层的形貌和结构进行表征测试。同时,利用显微硬度计、划痕测试仪系统地分析了涂层的显微硬度和界面结合性能,并研究了其摩擦磨损行为。研究结果表明:Ti/Ti N/Ti Al N/DLC复合涂层体系具有较高硬度(~2130HV)的同时结合性能最优(结合力~53.7 N),抗磨损能力最强。在相同试验条件下,无涂层的基体摩擦系数为0.45,单层DLC、Ti/DLC和Ti/Ti N/Ti Al N/DLC涂层的摩擦系数则分别为0.15、0.12和0.07。Ti/Ti N/Ti Al N/DLC复合涂层可有效提高304不锈钢的耐磨损性能,降低摩擦系数。     

金属组元配比对(ZrTiAl)N膜相组成和硬度的影响北大核心CSCD

采用多弧离子镀技术制备了不同金属组元配比的(ZrTiAl) N硬质反应膜,进而考查金属组元配比对(ZrTiAl) N硬质反应膜的相组成和硬度的影响规律。为保证(ZrTiAl) N膜层中Zr、Ti、Al组元含量配比的规律性变化,对膜层沉积过程中弧源靶及电流分别进行了设定。通过扫描电镜进行(ZrTiAl) N膜层表面形貌和断面形貌观察及成分测定。X射线小角度衍射方法用于膜层相结构测试分析。采用VICKERS 402 MVD硬度仪测定膜层的表面硬度。所制备的(ZrTiAl) N膜层保持了膜层表面形貌、断面形貌以及膜层厚度的一致性。(ZrTiAl) N膜层均为单一固溶体型(ZrTiAl) N面心立方相组成,具有单一的(111)面择优生长取向,其点阵常数随金属组元配比的变化基本符合Vegard定律。在金属组元配比的较大变化范围内,(ZrTi Al) N膜层的相组成和择优生长取向未改变,均具有较高的硬度。在以Zr N为基的(ZrTiAl) N膜层中,Ti N和Al N的含量较大并且接近相等时,膜层容易达到硬度极大值。     

镀Ti金刚石/Al复合材料的热性能

通过盐浴镀方法实现金刚石表面镀Ti,并采用模压铸造方法制备镀Ti金刚石/Al复合材料。研究镀层对复合材料微观结构和热性能的影响。结果表明金刚石表面镀Ti改善了复合材料的界面结合,降低界面热阻,从而提高了复合材料的热性能,包括降低热膨胀系数,提高复合材料的热导率。采用850℃盐浴镀Ti,镀覆时间180min得到的镀Ti金刚石/Al复合材料热导率高达488W/(m.K),在温度范围50～300℃之间,其平均热膨胀系数为9×10-6/K。     

采用BNi-7的Ti（C，N）基金属陶瓷与17-4PH沉淀硬化不锈钢的真空钎焊研究

采用镍基共晶钎料BNi-7对Ti（C,N）基金属陶瓷与17—4PH沉淀硬化不锈钢行了真空钎焊连接。研究了钎焊温度和焊缝厚度对焊接接头力学性能和微观结构的影响。结果表明,BNi-7对金属陶瓷粘结相具有较强的溶解能力,这是熔降元素（磷）能够在金属陶瓷侧大范围分布、钎焊接头获得良好界面结合的主要原因。随钎焊温度升高,磷在金属...     

Crack initiation mechanisms for low cycle fatigue of type 316Ti stainless steel in high temperature water

Low cycle fatigue (LCF) tests were performed for a type 316Ti stainless steel (SS) in high temperature water. Fatigue crack initiation behaviors in high temperature water were investigated. It was found that there existed several kinds of Ti-bearing precipitates, consisting of isolated TiN or duplex (Al, Mg)O/TiN, Mo-rich (Ti, Mo)C and Ti(N,C) in the steel. Fatigue cracks were mainly initiated at Ti-bearing precipitates, phase boundaries of austenite/α-ferrite phases and persistent slip bands (PSBs) in austenite. It is believed that synergism between the mechanical factors and electrochemical reactions played a key role in the process of fatigue crack initiation in high temperature water. Related fatigue crack initiation mechanisms for the 316Ti SS are discussed.     

Effect of surface nanocrystallization on the tribological properties of 1Cr18Ni9Ti stainless steel

Surface nanocrystallization of 1Cr18Ni9Ti austenite stainless steel was conducted by the supersonic fine particles bombarding (SFPB) technique. The friction coefficients and wear losses in air and vacuum were tested to analyse the effect of surface nanocrystallization on the tribological properties of 1Cr18Ni9Ti steel. The results show that the microstructure of the surface layer was refined into nano-grains successfully by SFPB treatment; furthermore, strain-induced martensitic transformation occurred during the treatment. The tribological properties of SFPB treated samples enhanced greatly, The dominant wear mechanism of the original 1Cr18Ni9Ti stainless steel is abrasive wear and adhesive wear, while it transfers to the combined action of fatigue wear, abrasive wear and adhesive wear after surface nanocrystallization by SFPB.     

Wear mechanisms of Ti(C, N) ceramic in sliding contact with stainless steel

Austenic stainless steel AISI 321 is one of the most difficult materials to cut. In order to investigate the wear behaviour of Ti(C, N) ceramic when cutting the stainless steel, wear tests were carried out on a pin-on-disc tribometer, which could simulate a real cutting process. The selected load range is 58.8–235.2 N; the selected speed range is 0.8–3.2 m s-1. The test results show that the wear of Ti(C, N) ceramic is mainly caused by adhesion between the rubbing surfaces; the wear increases with increasing load and increasing speed. When oil is used for lubrication, the friction coefficient of the sliding pairs and the wear rate of the ceramic are reduced. Scanning electron microscopy, energy-dispersive X-ray analysis and X-ray diffraction analysis are used to examine the worn surfaces. The wear mechanisms of Ti(C, N) ceramic sliding against the stainless steel are discussed in detail. This revised version was published online in November 2006 with corrections to the Cover Date.     

Filter effects on the wear and corrosion behaviors of arc deposited (Ti,Al)N coatings for application on cold-work tool steel

In this study, (Ti,Al)N coatings were deposited on Japanese Industrial Standard SKD11 modified cold-work tool steel using a cathodic arc deposition system with and without magnetic filter attachment. Coating morphology and properties such as coating structure, adhesion, hardness, abrasion and corrosion behaviors were analyzed to evaluate the effects of magnetic filter on the coatings. The results showed that magnetic filtering slowed down (Ti,Al)N deposition rate, but it improved component homogeneity, roughness and adhesion of the coatings. Although (Ti,Al)N coated specimens produced with or without filter both showed superior abrasion resistance in service, however, filtered (Ti,Al)N coatings yielded better corrosion protection of the steel than unfiltered ones in 3.5 wt.% NaCl aqueous medium.     

Ni和Ti的添加对Al2O3-Ti（C,N）复合材料性能的影响

研究了Ni和Ti的添加对真空热压烧结方法制备的Al2O3-Ti(C,N)陶瓷基复合材料的显微组织和力学性能的影响.发现添加Ni和Ti的复合材料主要由Al2O3、Ti(C,N)和Ni组成,没有发现存在金属Ti.Ti由于非常活泼,在热压烧结过程中可能与石墨模具产生的含C气氛反应生成TiC,或与高温下Ti(C,N)的少量分解产生的N2气氛反应生成TiN,这有利于减少复合材料中的气孔.适量添加Ni可通过液相烧结促进复合材料的致密化,提高复合材料的相对密度,并能通过产生裂纹偏转和裂纹桥联提高复合材料的断裂韧性.热压温度为1550℃、等摩尔比的Ni和Ti混合粉末添加量为5vol%时,Al2O3-Ti(C,N)-Ni-Ti复合材料的相对密度为99.6%,硬度为21GPa,抗弯强度为818MPa,断裂韧性为8.1 MPa.m1/2.     

特殊材料的真空热处理

真空热处理与可控气氛热处理、盐浴热处理相比有不少明显的特点,尤其对不锈钢等特殊材料的处理更是较佳的选择。本文针对真空热处理在精密合金（磁性、弹性材料等）、钛合金、高温合金及铜合金方面的应用进行了讨论和举例。介绍了市场真空热处理炉类别和功能,以利热处理行业技术人员的选择。     

Comparative study on structural transformation of low-melting pure Al and high-melting stainless steel under external pulsed magnetic field

A comparative study on the structural transformation of low-melting pure Al and high-melting 1Cr18Ni9Ti stainless steel under external pulsed magnetic field was carried out. The results showed that totally equiaxed grains were produced for pure Al, however, only thin columnar grains were generated for stainless steel even treated with higher magnetic intensity. It is deemed that grain refinement can be attributed to the heterogeneous nucleus created on the mould wall as well as their falling by the oscillating resulting from the magnetic field. In contrast, a dense chilling layer was generated at the primary solidification stage of the stainless steel due to the large temperature gradient between the high temperature melt and the mould and accordingly the nucleus falling was prevented. Therefore, only dendrites refinement possibly occurred.     

Diffusion bonding between Ti–6Al–4V alloy and ferritic stainless steel

In the present study, Ti–6Al–4V alloy was diffusion bonded to a ferritic stainless steel. The effect of bonding temperature on the microstructural development across the joint region was investigated. After diffusion bonding, microstructural analysis including metallographic examination, energy dispersive spectrograph (EDS) and shear strength was conduced. From the results, it was seen that bonding on the temperature was affecting the Fe and Ti mutual diffusion which controls the interface microstructure. The microstructure of the interface region was formed, consisting of Fe and Ti intermetallics.     

Transient liquid-phase insert metal bonding of Al2O3 and AISI 304 stainless steel

Transition liquid-phase insert metal bonding of Al2O3 and AISI 304 stainless steel based materials is investigated. This joining technique allows the continuous replenishment of the active solute which is consumed by the chemical reaction that occurs at the ceramic/filler metal interface. Replenishment is facilitated by employing a sandwich of filler materials comprising tin-based filler metal and amorphous Cu50Ti50 or NiCrB interlayers. During Al2O3/AISI 304 stainless steel bonding, the highest shear strength properties are produced using a bonding temperature of 500 °C. Thick reaction layers containing defects form at the ceramic/filler material interface when higher bonding temperatures are applied. Bonding at temperatures above 500 °C also increases the tensile residual stress generated at the periphery of Al2O3/AISI 304 stainless steel joints. The shear strength of joints produced using NiCrB interlayers markedly increased following heat treatment at 200 °C for 1.5 h. Heat treatment had little influence on the shear strength of the joint produced using Cu50Ti50 interlayers. This revised version was published online in November 2006 with corrections to the Cover Date.