磷对Ni—Mo—P合金镀层电沉积及镀层性质的影响

研究了镀液中次亚磷酸盐的浓度对电沉积Ｎｉ－Ｍｏ－Ｐ合金镀层影响及镀层中磷含量对镀层性质的影响。实验表明，镀液中次磷酸盐的浓度增加，镀层中磷含量增加，而钼含量大大降低，镀层更光亮；而镀层中磷含量的增加，镀层的耐蚀性及镀层的微观裂纹增加，且有利合金的非晶化。     

EN Ni—P镀层耐蚀性探讨

本所通过生产实践和实践证明化学Ｎｉ－Ｐ镀层耐蚀性不仅取决于镀层的磷含量，而且与镀层的组织结构，成分均匀性，表面形貌，热处理温度以及镀液的组成，操作条件，预处理的质量有关。     

铜及其合金化学镀工艺研究

研究了铜及其铜合金化学镀Ｎｉ－Ｐ合金的工艺条件，对镀层的性能、成分，结构，耐蚀性和结合力进行了分析研究。研究时效处理条件对镀层结构、硬度、摩擦磨损性能的影响，研究结果表明：该工艺可得到结合力好，磷含量在１２％以上的非晶态合金镀层基表面硬度，耐磨性，耐蚀性都有显著的提高。     

络合剂种类对化学镀Ni—P镀层阳极极化特性的影响

研究了在两种络合剂条件下得到的化学镀Ｎｉ－Ｐ镀层，在１０％ＨＣｌ、１０％ＮａＯＨ、及３．５％ＮａＣｌ介质中的阳极极化特性，动电位极化实验、极化前后镀层表面的金相显微镜和扫描电镜观察，以及极化前镀层表面胞状物显微硬度测量，结果表明：Ｎｉ－Ｐ镀层阳极极化特性不仅与镀层中的磷含量有关，而且还与镀层的表面形貌，成份分布以及组织结构等因素有关，并非高磷含量镀层在任何介质中都非常耐蚀。     

磷含量在化学镀层中对其性能的影响

采用酸性化学镀镍－磷合金电解液，通过改变不原剂浓度，制备了一系列不同磷含量的镍－磷合金镀层，以研究其中磷含量对镀层性能的影响。实验结果表明，镀层耐蚀性，硬度等性能与磷含量有直接关系，文他这种关系。     

Fe-Ni-Cr合金镀层耐蚀性能研究

研究了DMF－Glycine水溶体系电沉积Fe-Ni-Cr合金镀层耐蚀性能,结果表明：合金镀层耐蚀性能随合金镀层中铬含量的增加而提高,含铬量为27％的合金镀层与18－8不锈钢蚀性能相近,合金镀层经热处理印化后耐腐蚀性能增强。     

Ni—P—B4C化学复合镀镀层的研究

用扫描电镜、光镜及Ｘ光衍射仪对Ｎｉ－Ｐ－Ｂ４Ｃ化学复合镀层状态、内部组织结构进行了观察分析,结果表明,随镀液中Ｂ４Ｃ粒子添加量的增加,镀层中Ｂ４Ｃ含量及镀层表面瘤状生成物也增加。复合镀层中Ｂ４Ｃ粒子均匀分布于Ｎｉ－Ｐ基体。Ｂ４Ｃ粒子的存在未改变Ｎｉ－Ｐ基体的物相组成及其变化。同时测定了复合镀层的性能,结果表明,随镀层Ｋ４Ｃ含量增加,硬度提高,结合力下降,耐磨性显著提高。     

全光亮镍磷合金镀层的耐蚀性

采用个性盐雾实验、浸泡实验和阳极极化曲线测试了全光亮镍磷合金镀层耐蚀性.盐雾实验表明：磷含量为128mass%～153mass％的镀层耐蚀性能最好，磷合量提高到201mass％后，耐蚀性下降；热处理温度在200℃以下时，对镀层耐蚀性影响不大，超过300℃以上，镀层耐蚀性明显下降；浸泡实验表明Ni-P合金镀层与1Cr18Ni9Ti相比，在酸性、碱性和氯离子水溶液中耐蚀性能较好，但不耐硝酸、硝酸盐等强氧化性介质的腐蚀；阳极极化曲线测试表明，磷含量为12.8mass％的镀层在10％HCl、5％NaCl、20%NaOH和3.5％FeCl-3溶液中，均表现出了优异的耐蚀性能.磷合量为20.1mass％高磷镀层在20％NaOH中耐蚀性能优异.      

螯合滴定法测定合金镀层中的钯

用ＥＤＴＡ螯合Ｐｄ＾２＋及其它金属离子,然后用亚硫酸钠分解Ｐｄ－ＥＤＴＡ螯合物,释出的ＥＤＴＡ以Ｚｎ＾２＋标准溶液返滴定,大量各种金属离子完全不干扰。用于测定Ｐｄ－Ｃｕ合金镀层、Ｐｄ－Ｎｉ合金镀层、Ｐｄ－Ｓｎ－Ｃｕ合金镀层和ＰｄＴｉＳｉ合中的钯,获得相当满意的结果。     

Al—Mn合金镀层的研究

在２００℃共融的氯化物熔盐中,以ＭｎＣｌ２作为添加剂,电沉积出Ｍｎ含量为１８％～４０％的Ａｌ－Ｍｎ合金镀层。结果表明,当合金镀层中Ｍｎ含量超过３１％时,具有单一的非晶态镀层,单相非晶态镀层的耐蚀性、硬度等性能均优于双相镀层。Ｔｉ和Ｃｅ的加入,促进了Ａｌ－Ｍｎ金属玻璃的形成,使Ｍｎ含量较低的单相非晶体Ａｌ－Ｍｎ合金电沉积成为可能,提高了Ａｌ－Ｍｎ合金镀层的耐蚀性和硬度,使其点蚀电位提高了２００ｍＶ,     

金刚石复合镀层的研究

通过硬度和磨损试验,研究了金刚石含量,粒度,镀覆时间和镀后热处理对金刚石复合镀层耐磨性的影响,并据此筛选了最佳镀覆工艺。试验结果表明,在最佳镀覆条件下,金刚石复合镀层的硬度高达HV1889,为Ni-P化学镀层的2．8倍,耐磨性提高更多,可达Ni-P化学镀层的16倍以上,还探讨了金刚石复合镀层的耐磨机理。     

1Cr17Ni2铁素体含量的控制及其对性能的影响

航空发动机用1Cr17Ni2叶片经锻造及热处理后进行硬度检查,发现硬度偏低。通过在熔炼过程中调节Cr、Ni元素含量以及在后续热处理过程中逐步提高淬火温度,提出控制铁素体含量的具体办法,同时对不同铁素体含量的热处理后的棒料进行相关力学试验。结果表明:叶片硬度偏低与材料中存在较多δ?铁素体有关;1Cr17Ni2中δ?铁素体含量可以通过调节Cr、Ni元素含量及热处理过程中淬火温度进行控制,当原材料中铁素体形成元素含量高时,随着淬火温度的升高,特别是淬火温度高于1150 ℃,铁素体含量迅速增加;1Cr17Ni2合金钢中δ?铁素体含量过多时,其抗拉强度、冲击韧性、硬度等力学性能降低;通过合理调节原材料中Cr、Ni元素的含量,选择合适的热处理温度可以有效减少δ?铁素体含量,从而提高零件的力学性能。     

镍磷合金镀层表面强化性能的获得

镍磷合金化学镀是一项很有应用前途的表面强化技术,其镀层具有良好的性能。本文研究了镍磷合金镀层的显微硬度和耐磨性能,结果表明,镀层的性能和磷含量有关,还受到热处理的影响,且硬度和耐磨性变化并不一致,实际应用需选择恰当的工艺参数,以获得最佳的表面强化性能。     

The Relationship Between Phosphorus Content and Physical Properties of Electroless Nickel Deposits

The physical properties of electroless nickel deposits are intimately related to their composition. The work presented shows the relationship between deposit hardness, both as-plated and heat-treated and phosphorus content.

It is shown that in both cases maximum hardnesses are obtained with deposits of lower phosphorus content. Care must be taken with low phosphorus deposits to avoid over heat- treatment and recommendations for suitable times and temperatures are made.     

Microstructure evolution and hardening mechanisms of Ni-P electrodeposits

Ni-P alloy coatings with different phosphorus contents were prepared by electroplating in a nickel sulfate bath containing phosphorous acid (H₃PO₃). Hardening mechanism, such as dispersion hardening of Ni nano crystals in amorphous matrix of the as-deposited Ni-P coating and coarsening weakening of Ni₃P for the high P coating after 1 h of heat treatment at 400 °C were concluded from the experimental data. Hardening mechanism of Ni-P alloys were further discussed based on the microstructure evolution with increasing deposit P content and during the heat treatment by using high resolution TEM (HR-TEM). A maximum hardness was observed for the as-deposited and heat-treated Ni-P alloys with 4 wt.% and 6 wt.% P, respectively. These composition ranges corresponding to the microstructure with high hardness proposed are believed to be useful for the industrial applications and further study.     

Effect of phosphorus and heat treatment on microstructure of Al-25%Si alloy

It is known that phosphorus can refine the primary silicon and heat treatment can spheroidize the eutectic silicon. This paper presents an optimal combination of heat treatment processes and P refinement on hypereutectic Al-Si alloy. The optimal P addition amount, and the solution and aging temperatures for Al-25%Si alloy were obtained through the orthogonal experiment, and their modification effects were discussed. The results show that P addition has the greatest modification effect, followed by aging temperature, and the modification effect of solution temperature is the least. The optimized modification parameters are: addition of 0.6% P, solution at 540 oC and aging at 160 oC . In addition, the cooling curve, superheating and hardness of the alloy were also analyzed.     

镍硬铸铁Ⅳ的热处理工艺

以镍硬铸铁Ⅳ为研究对象,进行了热处理工艺试验,并探讨了热处理工艺对其组织及硬度的影响,拟定了镍硬铸铁Ⅳ的最佳热处理工艺。试验表明,硬化处理时合适的奥氏体化温度范围为800～820℃,为消除应力可考虑硬化处理后进行450℃回火;550℃+450℃的双重退火工艺,但对于零件硬度要求在60 HRC以上者不可取,对硬度要求在58 HRC左右的,则可采用。镍硬铸铁Ⅳ具有良好的热处理工艺性能,生产中易于掌握。     

14Cr17Ni2不锈钢叶片硬度不合格原因分析

利用直读光谱仪、光学显微镜和硬度计,对14Cr17Ni2不锈钢棒和叶片进行化学成分分析、显微组织高倍观察、以及不同热处理后硬度试验等检测试验,结合叶片的制造加工工艺过程对硬度不合格的原因进行了分析,并针对原因提出了改进措施。分析结果表明,钢棒在热加工和热处理过程中温度偏高,使叶片铁素体含量增加,是导致叶片热处理后硬度不合格的直接原因。通过调整钢的成分配比,适当提高镍当量值,合理控制钢坯和叶片的热加工及热处理工艺,取得了较好的效果,使叶片达到了所需的硬度。     

热处理对挤压铸造Mg93YZn6合金组织和性能的影响

采用挤压铸造法制备了Mg93YZn6合金,并对其进行高温热处理,分析了铸态和热处理态的Mg93YZn6合金的微观组织、显微硬度和力学性能。结果表明,该合金的挤压铸造和热处理后的组织中均只有α-Mg基体相和准晶I相生成。经500℃×4h热处理后,合金中的准晶相含量与铸态合金中变化不大。经550℃×2h热处理后,合金中的准晶相有所减少。与铸态合金相比,热处理后合金的硬度、抗拉强度和伸长率均提高。     

Heat Treatment Properties of 42CrMo Steel for Bearing Ring of Varisized Shield Tunneling Machine

The heat treatment properties of 42 CrMo steel for bearing ring of varisized shield tunneling machine were investigated by optical microscope(OM), scanning electron microscope(SEM), transmission electron microscope(TEM),and impact tests. The addition of 0.03 wt% C into 42 CrMo steel can increase the hardness. But it reduces the impact energy by 46 J because of the appearance of coarser carbides in the matrix and the carbides along the austenite grain boundary.The addition of 0.40 wt% Mn into 42 CrMo steel can improve hardenability. However, the toughness of steel is also reduced by 26 J mainly because of the coarsening of carbides and the strengthening of matrix. Both hardenability and toughness of 42 CrMo steel can be improved by adding 1.49 wt% Ni and reducing 0.32 wt% Cr. The depth of hardening layer can be raised to 45 mm, and the impact energy at-20 °C is 120 J. Thus, it is concluded that a good combination of hardness, hardenability, and toughness of 42 CrMo steel can be achieved by alloying with adding some content of C and Ni.Detailed content of C and Ni should be on the requirements of heat treatment properties of steel for bearing ring of varisized shield tunneling machine.