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1.
侯伟  潘功配  关华  杨莎 《热加工工艺》2007,36(12):42-44,48
研究了镀液pH值、施镀温度及施镀时间等工艺参数对碳纤维化学镀镍层厚度的影响,并研究了施镀时间与镀镍碳纤维导电性之间的关系,最终得出了较理想的碳纤维化学镀镍工艺参数。结果表明,采用优化后的工艺参数施镀,所得镀镍碳纤维镀覆均匀、光泽性好、镀层结合力强,导电性显著提高。  相似文献   

2.
化学镀Ni-P合金在铝合金剑杆头上的应用   总被引:3,自引:2,他引:3  
采用化学镀工艺方法在铝合金剑杆头表面镀一层Ni-P合金,代替进口的剑杆头。对铝合金剑杆头的预处理工艺、镀液的配方、施镀工艺以及镀后热处理工艺进行了研究,确定了简便易行的施镀工艺及镀后热处理工艺。所确定的镀液配方,性能稳定,可获得40μm以上厚度的镀层,且镀层与基体的结合力较好,其硬度可达1100HV以上,其 综合性能与进口件相当。  相似文献   

3.
镍铁-金刚石复合电刷镀的工艺研究   总被引:1,自引:0,他引:1  
复合电刷镀是电刷镀技术的一个重要分支,Ni-Fe-金刚石电刷镀镀层致密,耐磨性高,应用前景广阔。试验研究了Ni-Fe-金刚石复合电刷镀工艺中施镀电压、施镀温度以及镀笔与工件之间的相对速度对复合镀层性能(如金刚石含量、沉积速率和耐磨性)的影响,得到了高金刚石含量和高耐磨性镀层的最佳工艺参数,即施镀电压9~11V,施镀温度45~55℃,镀笔与工件的相对速度10~15m/min。  相似文献   

4.
河南信阳空军第一航空学院研究了镍-金刚石复合电刷镀工艺中施镀电压、施镀温度和镀笔与工件之间相对速度对复合镀层中金刚石含量和耐磨性能的影响,得到了制备高耐磨性镀层的最佳工艺参数,  相似文献   

5.
陶瓷颗粒表面的化学镀镍   总被引:3,自引:0,他引:3  
何志亮  邢建东  高义民 《铸造》2003,52(2):101-104
研究了陶瓷颗粒表面化学镀镍的工艺,并着重讨论了施镀时间、装载比及施镀温度对镀速及镀层形貌的影响,从而确定了最佳工艺参数。扫描电镜分析结果表明通过采用恰当的工艺,陶瓷颗粒表面能够获得表面形貌较好且镀层厚度均匀的镍沉积层。  相似文献   

6.
TL—6—2化学镀Ni—P合金工艺研究   总被引:4,自引:0,他引:4  
通过试验研究,选择出了合理的化学镀Ni-P合金工艺,配方与施镀工艺。该镀液性能稳定,便于施镀,调整,使用寿命可达6个周期。该工艺取材于工业级原料,成本低,适于工业生产应用。  相似文献   

7.
以2Cr13马氏体不锈钢为镀材、在45钢基体上进行温度低于600℃的电弧低温离子镀。用扫描电镜及X射线衍射仪分析了2Cr13/45钢镀层的相结构及施镀工艺参数对镀层致密性和铬元素分布的影响,并用动电位极化曲线法对镀层在3.5wt%NaCl溶液中的耐蚀性进行了测试。结果表明,沉积速率对镀层的致密性无明显影响,但施镀工艺参数对镀层相组成和铬元素的分布均有一定影响,并且当施镀时间t=60min、弧电流I=50A及样-靶间距H=175mm时,施镀层与电镀铬层的耐蚀性至少相当。  相似文献   

8.
采用复合化学镀工艺方法在铝合金转杯表面镀一层Ni—P—SiC合金,提高其耐磨性和使用寿命。对铝合金转杯的预处理工艺、镀液配方、施镀工艺以及镀后热处理工艺进行了研究。所获得工件镀层厚度达40μm以上,硬度可达1390HV0.05以上.其综合性能良好。  相似文献   

9.
PP塑料化学镀铜的工艺研究   总被引:1,自引:0,他引:1  
王喜然  张英伟 《表面技术》2010,39(5):77-79,114
采用配方为硫酸铜3 g/L、酒石酸钾钠25 g/L、甲醛(质量分数为36%~40%)10 g/L、氢氧化钠7 g/L的镀液,通过考察施镀温度、镀液pH值、施镀时间对镀速的影响,确定了最优工艺参数,并在优化的工艺条件下制备镀层,用扫描电镜和能谱仪对镀层的形貌及成分进行了分析.结果表明:最佳工艺是镀液温度50℃,pH=12,施镀时间45~50 min;采用此优化工艺条件制备的镀层,表观光亮、均匀,与基体结合力好,成分为单一的铜.  相似文献   

10.
化学镀非Ni—P/Ni—Mo—P合金形成机理   总被引:1,自引:0,他引:1  
通过对镀液中加入Na2MO4的化学沉积法对酸性Ni-Mo-P/Ni-P双层化学镀的工艺进行了实验研究,通过一系列实验,确定了用连续施镀法制备此多元合金镀层的工艺,通过对镀层的成分与结构关系及镀层成分与工艺参数关系的实验研究,从热力学角度提出了非晶态双层镀镀层合金膜材的形成机理。  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.
In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.  相似文献   

13.
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   

14.
Basing on the analysis of the traits of the roll forging process, a system-model of computer simulation has been established. Three-dimensional rigid-plastic FEM has been used for the simulation of the deformation process in the oval and round pass rolling, including the entering, rolling, and separating stages. The analysis was conducted using the Deform-3D ver.5.0 code. The important information concerned with the deformation area characteristic, material flow, and velocity field has been presented. Otherwise,the location of the neutral plane in the deformation area was shown clearly.  相似文献   

15.
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   

16.
The facile hydrothermal method was used to synthesize Fe3O4 nanoparticles with an average diameter of 11nm. The pure body-centered cubic (bcc)-Fe nanoparticles were prepared by reduction of Fe3O4 nanoparticles powder in H2 atmosphere. The structure, morphology and magnetic properties of the products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis-differential scanning calorimetry (TGA-DSC) and vibrating sample magnetometer (VSM). The results showed that the as-prepared Fe3O4 nanoparticles had a relatively homogeneous size. The particle diameters became bigger with the increase of reaction time. The growth kinetics of the Fe3O4 nanoparticles was also briefly discussed. The products exhibited superparamagnetic properties at room temperature and the specific saturation magnetization was dependent on the particle sizes.  相似文献   

17.
In this work, the influence of sub-zero Celsius treatment and tempering on the mechanical and thermal stability of retained austenite in bearing steel were assessed by tensile test and DSC. Compared with traditional quenched and tempered treatment, sub-zero Celsius treatment obviously decreases the volume fraction of retained austenite. Moreover, the mechanical stability of retained austenite was enhanced due to the accumulation of compressive stresses in retained austenite after sub-zero Celsius treatment and tempering. Meanwhile, the morphology of retained austenite changed from film-like to blocky with austenitization temperature increasing, and the mechanical stability of film-like retained austenite is higher than that of blocky one. The DSC results showed that the activation energy of retained austenite decomposition slightly increased through sub-zero Celsius treatment and tempering. This result may probably be ascribed to partitioning of carbon during tempering. However, the temperature at which retained austenite starts to decompose is unchanged.  相似文献   

18.
陈新梅  李心沁 《金属学报》2008,13(9):981-984
目的:研究伊文思蓝鼻腔给药壳聚糖载体的促吸收作用及其对鼻腔黏膜的毒性。方法:小鼠鼻腔给伊文思蓝的壳聚糖溶液后, 采用荧光显微镜观察脑部伊文思蓝的分布;紫外法测定小鼠脑部其含量;通过鼻腔黏膜切片考察壳聚糖对大鼠鼻腔黏膜毒性。结果:壳聚糖对伊文思蓝经鼻吸收入脑具有促进作用, 伊文思蓝在脑前、中、后部均有分布;壳聚糖载体对大鼠鼻黏膜毒性较小。结论:壳聚糖是水溶性药物经鼻吸收入脑的优良载体。  相似文献   

19.
The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.  相似文献   

20.
The plastic deformation of the pipe made of Cu-based alloy hardened by incoherent nanoparticles and subjected to the uniform internal pressure was investigated. The limits of elastic and plastic resistance are determined. The insignificant excess in the limit of the elastic resistance enables the plastic deformation in the most part of the pipe wall. The densities of shear-forming dislocations and prismatic dislocation loops are higher in alloys strengthened with coarse particles than in alloys strengthened with fine particles. At small distances between the strengthening particles, this effect is the most pronounced.  相似文献   

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