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高磷含量Ni-W-P镀层热处理晶粒尺寸及微应变的演变 总被引:1,自引:1,他引:1
用XRD定量分析法研究了两种成分的高磷Ni-W-P镀层在不同热处理条件下的晶化组织、晶粒尺寸及微应变的演变规律.结果表明:在400℃晶化时,尽管P含量有所差异,但镀层的晶化程度趋于一致,且在400~500℃之间形成的Ni3P晶粒尺寸大于Ni;加热温度超过500℃,则Ni的尺寸大于Ni3P.温度达到700℃时,仍有残存的非晶相,其P含量越高,Ni3P转变的体积分数越大于Ni的分数.用XRD方法实测得到的残余应力温度范围在400~700℃之间,残余应力随温度升高而降低的变化规律与通过XRD计算的晶格应变的变化规律一致.镀态时镀层的晶格应变最大,非晶态程度越高,晶格应变越大. 相似文献
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用化学沉积法制备Ni-W-P合金镀层。利用扫描电镜(SEM)及X射线衍射(XRD)技术,并结合JADE软件定量分析镀层微观组织特征,研究了退火晶化前后显微组织对镀层耐磨性的影响。结果表明,化学沉积Ni-5.24wt%W-6.71wt%P镀层镀态下的晶化程度约为24%,退火温度升高到700℃时,晶化程度约为94%,未达到完全晶化。在Ni3P相晶化反应温度下,Ni3P相的晶粒尺寸大于Ni相,高于其晶化温度时,Ni相晶粒尺寸大于Ni3P相。退火温度超过600℃时,两相的晶粒尺寸迅速粗化。镀层磨损率随退火温度的升高而减小,500℃时出现最小值,超过500℃时,磨损率又开始增大。镀层较高的耐磨性除了与其硬度有关外,还取决于适当的晶化程度和较小的晶粒尺寸。 相似文献
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用化学沉积法制备了Ni-9.3P、Ni-4.9W-6P及Ni-4.9W-6P/Ni-9.3P(质量分数,%)双合金镀层,分别对其进行300、400、600 ℃的退火处理。借助XRD定量分析,对比分析了双镀层热处理晶化程度、各相质量分数及晶粒尺寸。通过镀层硬度测试、0.5 mol/L的H2SO4溶液浸泡腐蚀试验以及表面形貌观察,研究比较了镀层的硬度及耐蚀性。结果表明,Ni-P镀层在300 ℃退火处理1 h时出现Ni3P相,而Ni-W-P单镀层及Ni-W-P/Ni-P双镀层均没有Ni3P相的析出;直到400 ℃时,才开始发生Ni3P相晶化反应。3种镀层的峰值硬度均出现在400 ℃退火温度下,随退火温度从400 ℃升高到600 ℃时,镀层硬度下降,双镀层硬度介于两单镀层之间。3种镀层最差的耐蚀性均出现在Ni3P刚刚开始析出的温度,而较好的耐蚀性则出现在600 ℃较高的退火温度下。 相似文献
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化学沉积Ni-P/Ni-W-P合金的热处理晶化及磨损行为 总被引:2,自引:0,他引:2
用XRD定量法分析了W的共沉积对Ni-P基合金镀层热处理晶化程度、晶粒尺寸的影响,通过镀层硬度测试、干摩擦条件下的磨损实验以及SEM形貌观察研究了镀层的磨损行为.结果表明:W的共沉积提高了镀态和热处理的Ni-W-P镀层的晶化程度,加速Ni相的晶化过程,提高了Ni3P相的晶化反应温度,并使Ni-W-P镀层硬度大于Ni-P镀层的硬度.非晶态Ni-9.27%P镀层晶化前后的磨损行为主要表现为粘着磨损;当P含量与其相同(相近)时,W的加入不改变Ni-5.13%W-9.32%P合金在镀态及低温热处理时的粘着磨损行为,但对高温(600 ℃以上)热处理镀层起主导作用的磨损形式为微切削磨损机制. 相似文献
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化学沉积 Ni-Mo-P 和 Ni-P 镀层退火晶化组织及耐蚀性 总被引:1,自引:1,他引:0
目的研究化学沉积Ni-4.11%Mo-6.50%P和Ni-9.19%P合金镀层退火晶化转变特征,通过定量表征镀层的晶化程度、晶粒尺寸及结晶相的质量分数,建立显微组织与耐蚀性的关联。方法采用XRD衍射技术和Jade软件分析,定量表征镀层的晶化组织特征,由SEM/EDS测试确定镀层的成分及表面形貌,通过浸泡腐蚀实验及金相显微观察,对比两种镀层的耐蚀性。结果 Ni-Mo-P镀层在低于400℃退火时,只有Ni相结晶;在≥400℃退火时,发生Ni3P晶化反应,同时伴有Ni-Mo固溶体的形成,600℃时的晶化程度为88.13%。相比之下,Ni-P镀层中Ni3P相开始析出的温度降至300℃,600℃时的晶化程度达到91%。在相同温度进行热处理时,Ni-Mo-P镀层晶粒尺寸小于Ni-P镀层。在发生Ni3P晶化反应的温度下,两种镀层中Ni3P的晶粒尺寸总是大于Ni相。在0.5 mol/L的H2SO4中,对于Ni-Mo-P镀层,除300℃外,其他温度下的热处理均能显著改善其耐蚀性;而对于Ni-P镀层,镀态下具有最好的耐蚀性能。在10%的HCl溶液中,退火温度为600℃时,Ni-Mo-P镀层的耐点蚀性能更好;而Ni-P合金则相反,镀态及低温200℃退火后的耐点蚀性能最好。结论 Mo的共沉积提高了Ni-Mo-P镀层Ni3P的析出温度,降低了镀层的晶化程度及晶粒尺寸;与Ni-P镀层相比,高温退火的Ni-Mo-P镀层表现出了优异的耐点蚀性能,但耐硫酸均匀腐蚀的性能较差。 相似文献
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电沉积非晶态镍磷合金晶化过程研究 总被引:1,自引:0,他引:1
利用差示扫描量热仪(DSC)和X射线衍射仪(XRD)研究了w(P)=12.3%的电沉积非晶态镍磷合金镀层的晶化过程.结果表明,w(P)=12.3%的非晶态镍磷合金镀层的DSC曲线具有4个放热峰:镀层在260℃热处理时仍保持非晶结构;在270、290、300和320℃热处理后,析出亚稳相Ni12P5和Ni5P2;在360℃热处理后,亚稳相Ni12P5减少,亚稳相Ni5P2消失,析出Ni3P和Ni;镀层经420℃热处理后,亚稳相Ni12P5和Ni5P2完全消失,晶化产物为Ni3P和Ni. 相似文献
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用熔融快淬法制备了FeCuNbSiB非晶纤维,分别在300℃,400℃,450℃,500℃进行了1h退火处理。用扫描电镜分析了退火前后的纤维表面形貌。用X射线衍射分析了纤维在此温度段的晶化行为,估算其晶粒尺寸约为37nm。用差示扫描量热仪分析了纤维的晶化温度在530℃左右。若退火温度升高到约700℃时则有其它相析出,使软磁性能恶化。随退火温度的升高,纤维的比饱和磁化强度减小,纳米晶相体积分数增大,非晶相减少。对饱和磁化强度的影响占主导地位的是纳米晶相。 相似文献
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在常规晶化退火工艺条件下纳米双相永磁合金快淬非晶薄带的晶化过程中,α-Fe相通常在低温优先析出,这导致了α-Fe晶粒过于粗大并严重损害了材料磁性能。针对这一问题,近期有一些学者对极端晶化条件下非晶快淬薄带的晶化行为和机制进行了仔细的研究。本文对这些研究进行了综述和分析。 相似文献
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脱硫车间氨结晶罐开裂是两个方面原因造成的,其一是在腐蚀环境下长期工作,产生的氢鼓泡;其二是材料本身存在缺陷。为此采取了有效的方法进行了处理。 相似文献
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金属型球铁磨球非平衡凝固特性的研究 总被引:3,自引:1,他引:3
探索了金属型球铁磨球非平衡结晶过程,并就磨球的非平衡凝固特性进行了较深入的分析研究。过共晶球铁凝固时出现非平衡奥氏体;亚共晶球铁出现晕圈铁素体和非平衡渗碳体相;在柱状晶与等轴晶过渡区中存在着偏聚物。为改善球铁磨球的显微组织及性能,球铁成分应控制在共晶或稍过共晶处。 相似文献
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调整电解槽的下料量可平衡电解槽各项技术条件,从而达到稳定电解生产的目的。充分了解电解槽下料量对电解质成分的影响,总结生产过程中下料间隔的调整方法,对于把握电解槽槽况的发展趋势以及对电解质成分的调整将会起到较好的作用。 相似文献
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Deng-Kui Zhang Guo-Qing Wang Ai-Ping Wu Ji-Guo Shan Yue Zhao Tian-Yi Zhao Dan-Yang Meng Jian-Ling Song Zhong-Ping Zhang 《金属学报(英文版)》2019,32(6):684-694
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
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After nearly two years'tense construction the first phase of industrialized base of Shenyang Research Institute of Foundry 《中国铸造》2008,5(1):63-64
After nearly two years' tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry (SRIF), located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation. 相似文献
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Z. Sun S.L. Zheng Y. Zhang 《金属学报(英文版)》2007,20(3):187-192
Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process. 相似文献
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R. González-Martínez 《金属学报(英文版)》2007,20(4):235-240
The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke. 相似文献