超音速喷涂WC－Co／45~＃钢的剪切强度及断口分析

测定了超音速喷涂ＷＣ－Ｃｏ／４５＃（或弹黄钢）的界面剪切强度。断口分析表明剪切断裂发生在４５＃钢基体和涂层的界面上。ＷＣ－Ｃｏ涂层主要由细小的ＷＣ相、块状含铁相和分布均匀的钴相组成。在ＷＣ－Ｃｏ／４５＃钢界面层中，块状含铁相是α－Ｆｅ和马氏体。马氏体的形成是ＷＣ中脱出的碳与铁结合形成的奥氏体再空冷的结果     

激光重熔预处理制备生物陶瓷涂层

在激光表面重溶预处理的ＴＣ４合金基材上预置涂敷ＣａＨＰＯ４２Ｈ２Ｏ－ＣａＣＯ３－Ｙ２Ｏ３混合粉末，再经激光熔覆处理制备了生物陶瓷复合涂层。研究了该生物陶瓷涂层的织织和性能。结果表明，采用激光表面重熔预处理作过渡层制备的生物陶瓷涂层的界面结合良好，表层为ＨＡ和β－ＴＣＰ组成的活性生物陶瓷复合涂层。     

电沉积-水热合成法制备的生物陶瓷涂层与基体界面结合强度

采用电沉积水热合成法和高温煅烧相结合的方法,制备了生物陶瓷涂层,研究了涂层与基体间过渡层的物相组成和界面结合强度。用X射线(XRD)、扫描电镜(SEM)和粘接拉伸法进行分析。研究结果表明:水热合成后,界面结合强度较低,为7.04MPa。在空气中煅烧,700℃以下时,界面出现极薄TiO_2层,同时随着煅烧温度的升高,界面结合强度提高;800℃以上时,由于厚而疏松的TiN过渡层的出现,界面结合强度反而下降。为获取对骨生长有利的HAP+β-Ca_3(PO_4)_2双相结构,且界面结合强度高的涂层材料,将原始试样用NaOH碱液处理,电沉积水热合成后,在氢气中于900℃煅烧,过渡层为薄且致密的TiO_2层,可获得高的界面结合强度,为22.39MPa。     

硅化物涂层对Nb?Ti?Al合金力学性能的影响

采用真空电弧炉熔炼法制备低密度Nb?Ti?Al合金铸锭,利用料浆烧结法在铸锭表面涂覆Si?Cr?Ti复合硅化物涂层,使用万能电子拉伸试验机对合金试样和涂层试样进行力学性能测试,研究硅化物涂层对试样力学性能的影响。结果表明,与合金试样相比,涂覆涂层后的低密度铌合金室温力学性能（抗拉强度、屈服强度及延伸率）显著下降。为进一步研究涂覆涂层合金力学性能下降的原因,采用扫描电子显微镜和能谱仪对合金试样和涂层试样进行显微组织观察、涂层/基体界面成分分析及C含量（质量分数）测定。结果表明,涂层试样力学性能下降的主要原因包括涂覆涂层后合金晶粒显著长大,合金中强化元素Al的向外扩散,脆性相Nb₃Al的形成以及Si?Cr?Ti涂层对合金产生的“渗沉效应”。     

真空熔覆碳化钨僭基合金复合涂层抗疲劳性能的研究

在45钢试样表面采用真空熔覆法制得碳化钨／钴基合金复合涂层，按照45钢热处理工艺对复合涂层进行正火处理，并借助扫描电子显微镜、x射线衍射仪等先进的测试手段对复合涂层的组织结构和表面形貌进行观察分析。应用疲劳试验机对不同碳化钨含量的复合涂层进行弯曲疲劳试验。结果表明：复合涂层在正火处理后的弯曲疲劳强度大大提高，比熔覆状态合金涂层高150～200MPa；在高周疲劳时比正火45钢的疲劳强度高80MPa左右；正火处理后，含15％（质量分数）WC的复合涂层的弯曲疲劳强度最大；复合涂层的疲劳强度除与硬度相关外，还与复合涂层和45钢基体的界面结合强度、涂层内部缺陷等因素有关。     

涂层压入仪的研制及其应用

报道了涂层压入仪的研制背景、结构原理、主要技术特性及其应用举例,该仪器具有连续加载卸载功能并配有声发射和光学系统,能测量并记录连续的载荷与压入深度关系曲线,能用声发射系统对测试过程中涂层试样的开裂和剥落进行动态监测,并确定对应的载荷,用涂层压入仪作界面压入测得厚涂层与基体界面开裂的临界载荷pw可反映涂层的结合强度;也可正面压入考察薄膜与基体的结合,区分薄膜开裂和剥落并精确测定其对应的载荷值,用加载过程中发生初始剥落的载荷表征膜的结合强度,涂层压入仪还可用于膜韧性、膜和膜,基断裂韧性、离子氮化层脆性等的评价,测定块体材料硬度、塑性功、弹性功、弹塑性比等性能指标。     

超音速喷涂WC—Co／45^#钢的剪切强度及断口分析

测定了超音速喷涂ＷＣ－Ｃｏ／４５＾＃的界面剪切强度。断口分析表明剪切断裂发生在４５＾＃钢基体和涂层的界面上。ＷＣ－Ｃｏ涂层主要由细小的ＷＣ相，块状含铁相和分布均匀的钴相组成。     

热处理对超音速火焰喷涂 NiCoCrAlY 涂层组织性能的影响

采用超音速火焰喷涂制备了NiCoCrAlY合金涂层,采用真空热处理工艺对涂层进行了后处理,研究了热处理前后涂层的结构形貌、界面以及涂层结合强度的变化。研究结果表明:热处理后涂层的缺陷和孔隙由8.3%降低至1.4%;SEM和EDS分析表明,涂层与基材之间发生了元素互扩散,涂层与基体形成了约20μm的扩散层,涂层的结合强度由42.1MPa提高到55.6MPa。热处理后,涂层/基体界面形成的扩散层改善了界面结合状态,有助于消除界面处的残余应力,并形成冶金结合,从而提高涂层的结合强度。     

等离子喷涂 Mo 包覆 Ni20Cr 自粘结粉末 制备的粘结层结合性能

针对如何提升金属粘结层结合强度的问题, 本研究提出了使用 Mo 包覆 Ni20Cr 复合粉末作为新型粘结层 材料的方法。 高熔点 Mo 包覆层可以减少喷涂过程中核芯元素的蒸发, 在大气等离子喷涂条件下获得超高温熔滴, 有助于涂层与基体以及涂层内部实现冶金结合。 采用机械合金化法制备了 Mo 包覆 Ni20Cr 复合粉末, 并在大气 等离子喷涂条件下制备涂层考察其结合强度。 通过一维传热模型预测了镍基合金熔滴碰撞在镍基合金、 奥氏体不 锈钢和低碳钢基体上实现铺展熔合冶金自结合所需要的温度, 采用 DPV-2000 测试系统对粒子飞行过程中的温度 进行测量, 使用扫描电子显微镜 (SEM) 对涂层的微观结构进行了表征。 粒子温度测量结果表明, 在大气等离子 喷涂条件下, Ni20Cr-Mo 熔滴可加热至 2620 ℃以上, 满足碰撞铺展过程中引起基体表面熔化而产生冶金结合的 温度条件。 涂层结合强度拉伸试验中所有试样都从胶中断裂, 涂层结合强度大于 76.1 MPa。 组织观察结果表明涂 层组织结构致密, 不仅大量粒子层界面间产生了冶金结合, 涂层与基体界面处也观察到一定深度的熔坑, 表明涂 层与基体以及涂层层间界面均实现了冶金结合, 由此显著提高了结合强度。     

钢基Fe/Al2O3复合材料的界面特征

用喷涂法和溶胶-凝胶法相结合的工艺制备钢基Fe／Al2O3，梯度复合材料，并对其性能进行分析。采用电子万能材料试验机进行结合测试，利用金相显微镜分析复合材料断面组织，用X射线衍射仪分析陶瓷涂层成分。结果表明，Fe／Al2O3，梯度涂层与钢基体界面结合强度较高，平均达到17.62MPa；涂层与基体以及涂层与涂层之间相互融合，并未出现明显的界面联接层，实现了涂层与钢基体在同一区域共存，有助于提高涂层与基体的结合强度；Fe／Al2O3，梯度涂层主要由α-Al2O3、AlFeO3、AlFe3和Al86Fe14等物相组成，对材料的结构和性能都非常有利。     

Chinalco Signed Framework Agreement for Strategic Cooperation with Harbin Municipal Government

正Last month,Chinalco signed framework agreement for strategic cooperation with Harbin Municipal Government in Harbin Xiong Weiping,Chairman of Chinalco,said that based on the strategic deployment to build world top-class mining company with the highest growth potential,Chinalco was now concentrating all efforts on making strategic transition and structural adjustment,strategic cooperation with the local governments where     

Jiangxi Promotes Jiangxi Copper Corporation To Become The World's Most Competitive Mining Company

<正>According to the latest info from Jiangxi Province State-owned Assets Supervision and Administration Commission,Jiangxi Copper Corporation was approved to become the first pilot enterprise for deepening reform.Contents of the pilot work is"Three Self"(self expansion,self decision-making,self     

Journal of Rare Earths Contents List of Vol.32(2014)

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Contributions to Baosteel Technical Research wanted

正Baosteel Technical Research,a quarterly journal,which is issued domestically and abroad,is run and sponsored by Baosteel Group Corporation.Baosteel Technical Research mainly reports the achievements in technological innovation,academic research,new product development and industrial equipment improvement by Baosteel.It will continue to follow up on hot topics and serve the company’s technological development and progress.Its readers include experts in     

Ministry of Industry and Information Technology: No Short Term Solution For Our Country’s Excess Nonferrous Metal Smelting Capacity

【正】According to the Ministry of Industry and Information Technology,the Ministry has released the 2013 Operation Report on China’s Industrial Communication Indu...     

Chinalco Signed Framework Agreement for Strategic Cooperation with Gansu Province

正Recently,Chinalco and Gansu Provincial People’s Government signed"Framework Agreement for Strategic Cooperation on Reform,Restructuring and Transition Development of Chinalco’s Electrolytic Aluminum Enterprises in Gansu",signifying that the strategic cooperation between Chinalco and Gansu Province had made new substantive progress.     

Unavoidable Economic Cycle:30% Of Nonferrous Metal Companies Were Involved In Restructuring

正Owing to continual downturn in real estate and bulk commodity markets,a number of traditional industries in China suffered unfavorable impact in performance.With the progressive disclosure of third quarter report,the no-pleasant-surprise performance of     

Baotou Rare Earth Became the World's Biggest High Performance Magnetic Material Base

正The High Performance Magnetic Material Phase II Project,an industry upgrading project implemented by Inner Mongolia Baotou IronSteel Rare Earth(Group)Hi-tech Co.,Ltd,recently basically finished equipment commissioning,signifying that the enterprise had developed the production capacity of15000 t/a Nd-Fe-B strip casting alloy and 5000t/a Nd-Fe-B magnet,thus becoming the world’s     

Introducing Two Central Enterprises to Integrate Rare Earth Industry,Shandong Rare Earth Group Breaks Surface

正With the signing of"Letter of intention for Propelling Integration of Shandong Rare Earth Enterprises"between Shandong Province Commission Of Economy and Informatization,China IronSteel Research Institute Group("China Steel Institute"),and China Rare MetalsRare Earth Co.,Ltd("China Rare Earth"),the"Shandong Rare Earth Group"jointly set up by the 3 units thus broke surface.On August 9,reporters of the China Economic Herald learned from Shandong Province     

Aluminium Production by Province or City in 2014

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