Xianming Meng
材料科学技术（英文）
In the present study, 304 stainless steel coatings were deposited on interstitial-free steel substrates by cold gas dynamic spray technology. The effect of gas temperature on microstructure, micro-hardness, cohesive strength, and electrochemical property of the coatings were investigated and compared. The results showed that increasing gas temperature had a great contribution to enhancing the bonding strength between the deposited particles and making the microstructure more density. Therefore, the porosity of the coatings decreased from 6%±0.5% to 2%±0.3%, and the tensile strength of the coatings increased from 56±4 MPa up to 73±3 MPa. In addition, the corrosion resistance of the coatings was also deeply influenced by process gas temperature. The corrosion kinetics of the coatings were affected by both of the plastic deformation of deposited particles and the porosity in the coatings.
关键词:
Cold spray
M.Abou Zied
,
null
材料科学技术（英文）
Microstructure and mechanical properties of ball-milled Al-8 wt pct Ni ribbon have been investigated by X-ray diffraction (XRD) and continuous Vickers hardness test, respectively. The results indicate that, the main phases of this alloy are α-Al and orthorhombic-Al3Ni. The lattice parameter of α-Al increases with increasing milling time. From the elastic constant of Al, the average contrast factors of the (111), (200), (220), (311) and (222) Bragg0s reflections for pure edge and pure screw dislocations in fcc crystals with a/2<110>{111} slip system were calculated. The average grain size and dislocation parameters as a function of milling time have been investigated using the modified Williamson-Hall plot and the Warren-Averbach equation, respectively. An attempt has been made to correlate the micro-hardness of milled ribbon with their grain size through the Hall-Patch relationship: HV0:01 = 742.45 < D >-1/2 +401.55 (kg/mm2).
关键词:
Aluminum
,
null
,
null
,
null
Xianming Meng
材料科学技术（英文）
In the present study, 304 stainless steel coatings were deposited on interstitial-free steel substrates by cold gas dynamic spray technology. The effect of gas temperature on microstructure, micro-hardness, cohesive strength, and electrochemical property of the coatings were investigated and compared. The results showed that increasing gas temperature had a great contribution to enhancing the bonding strength between the deposited particles and making the microstructure more density. Therefore, the porosity of the coatings decreased from 6%±0.5% to 2%±0.3%, and the tensile strength of the coatings increased from 56±4 MPa up to 73±3 MPa. In addition, the corrosion resistance of the coatings was also deeply influenced by process gas temperature. The corrosion kinetics of the coatings were affected by both of the plastic deformation of deposited particles and the porosity in the coatings.
关键词:
Cold spray
Ying XU
,
Mingli LI
,
Yan GUO
,
Fengji LU
材料科学技术（英文）
The nano-TiO2/unsaturated polyester resin (referred to as nano-TiO2/UPR hereafter) was prepared with the ``reaction method", by which a chemical bond generated between nano-TiO2 and UP was inserted in the UP long chain. The performance of the nano-TiO2/UPR was determined by such a new structure. The research results showed that the reactivity of nano-TiO2/UPR is higher than that of UPR. The impact strength and bending strength of nano-TiO2/UPR are greatly enhanced as compared with that of UPR. Thermal resistance and dielectric property of nano-TiO2/UPR are the same as that of UPR.
关键词:
Nano-TiO2
,
null
,
null
,
null
郑蕊
,
李艳
,
嵇阿琳
,
张国辉
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2015.02.012
比较了两种不同工艺制备的针刺无纬布C/C复合材料.研究表明,在沥青浸渍/碳化之前对针刺预制体进行CVI预增密处理后,其C/C复合材料轴向拉伸强度提高了234％,层剪强度提高了126％;热扩散率明显升高,轴向线胀系数下降,表现出良好的综合性能.
关键词:
致密化
,
针刺无纬布
,
C/C复合材料
,
性能
张帅
,
任毅
,
王爽
,
刘文月
,
高红
上海金属
研究了合金减量化对高强度大壁厚X80管线钢的组织和性能的影响.结果表明,Ni、Mo、Cu、Cr合金含量降低,组织中先析铁素体增加且长大,强度下降,但韧性变化不大;Ni、Mo、Cu、Cr合金总量由0.61％减少到0.30％,大壁厚X80适宜的微观组织由以针状铁素体+粒状贝氏体为主转变为贝氏体+少量先析铁素体,通过试制工艺的优化可以保证试验钢性能满足技术要求,合金减量化具备可行性.
关键词:
X80管线钢
,
合金减量化
,
组织
,
性能
陈剑
,
张恒华
上海金属
利用电阻加热设备对160 mm×15 ram×3 mm矩形试样进行加热后局部喷水冷却,研究试样不同位置的温度变化情况以及不同位置冷却后的组织性能变化.通过腐蚀原始奥氏体晶粒研究加热时间和电流密度对晶粒的影响.结果表明:采用电阻加热,试样温度场呈现"中间高,两边低"的分布规律,中间存在一定长度的均温区.电流密度一定时,最高加热温度也是一定的,且该温度随着电流密度的增加而增加.加热时间越长,电流密度越大,原始奥氏体晶粒越大.
关键词:
电阻加热
,
微合金钢
,
组织
,
性能
王斌
,
王凤德
,
张阳
,
张承双
,
袁海根
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2014.03.009
以改进型芳纶Ⅲ纤维(F-3A)的研制及工程化应用为背景,开展了F-3A纤维及其复合材料性能研究,采用改进型环氧树脂体系与F-3A纤维复合进行了NOL环及其全尺寸复合材料缠绕构件试验考核.试验结果表明,F-3A纤维的力学性能优异,工艺性能稳定,能够满足复合材料结构工程应用要求.
关键词:
改进型芳纶Ⅲ纤维
,
复合材料
,
构件
,
性能
沈斌
,
项斯捷
,
张恒华
上海金属
针对实际生产条件对轧后连续冷却过程中高强度船板钢的组织性能进行了模拟.采用光学显微镜对试验钢的微观组织进行观察,运用Image-Pro Plus图像分析软件对铁素体进行定量化分析,并使用万能试验机对材料进行力学性能测试.试验结果表明,试验钢的组织含量、晶粒尺寸及力学性能的模拟结果与实测结果相符.这对工厂调整高强度船板钢的生产工艺,提高其力学性能,具有重要的参考价值和指导意义.
关键词:
高强度船板钢
,
连续冷却
,
组织
,
性能
,
模拟
