共查询到20条相似文献,搜索用时 171 毫秒
1.
氧乙炔火焰喷焊镍基复合涂层的显微组织和腐蚀性能研究 总被引:1,自引:0,他引:1
目的 研究Ni60和Ni60WC喷焊涂层的显微组织、防腐和耐磨性能及其腐蚀机理,为恶劣工况下服役的零件选择合适的喷焊涂层提供参考.方法 采用氧乙炔火焰喷焊工艺在16Mn钢基体上制备Ni60和Ni60WC涂层,用X射线衍射仪、金相显微镜和扫描电子显微镜分析了喷焊涂层的相结构和显微组织,并采用电化学工作站、盐雾腐蚀试验机、磨粒磨损试验机测试了两种喷焊涂层的防腐和耐磨性能.结果 喷焊层与基体间都存在冶金结合层和热影响区,Ni60涂层的显微组织为NiCr固溶体基体上弥散分布着大量细小粒状和杆状碳化物和硼化物.Ni60WC喷焊涂层组织中,除了具有与Ni60涂层类似的基体相和细颗粒硬质相外,还较均匀地分布着不同尺寸的WC颗粒.Ni60和Ni60WC涂层的磨损率分别为16Mn钢的8.3%和2.3%,自腐蚀电流密度分别为16Mn钢的1.0%和7.6%.另外,基体相和硬质相之间的电偶腐蚀是两种镍基喷焊涂层的主要腐蚀机理.结论 这两种镍基喷焊涂层均能显著提高16Mn钢的抗磨和防腐性能,其中,Ni60喷焊涂层耐腐蚀性更好,Ni60WC喷焊涂层耐磨损性能更好. 相似文献
2.
3.
4.
5.
6.
7.
等离子弧喷焊镍基合金层组织及耐磨性试验研究 总被引:5,自引:0,他引:5
在16Mn钢表面等离子弧喷焊自熔性镍基合金喷焊层(Ni60)及加入w(WC)25%的镍基合金喷焊层(NWC25),对两种合金喷焊层进行了显微组织,X射线衍射分析,硬度及不同腐蚀介质下的腐损试验。结果表明,合金喷焊层显微组织均为γ固溶体基体和各种化合物相,如Fe23(C,B)6,(Cr,Fe)7C3,Cr7C3,NiB,WC等。NWC25喷焊层具有较高的硬度,在腐蚀介质中耐磨性明显高于Ni60,合金喷焊层在弱酸碱介质中的耐磨性比在中性水中都有所降低,在酸性介质中降低较为明显。 相似文献
8.
目的研究镍基自熔性合金喷焊涂层成形机理,比较不同合金材料制备涂层的综合性能,以获得综合性能最佳的喷焊材料。方法以四种不同成分的镍基自熔性合金粉末作为喷焊材料,通过氧乙炔火焰在45钢基材表面进行喷焊。使用金相显微镜、X射线衍射、扫描电子显微镜等对喷焊层进行显微结构分析,并利用维氏硬度计、磨损试验机等对喷焊涂层性能进行对比分析。结果氧乙炔火焰制备的涂层与基体呈现良好的冶金结合,涂层和基体在喷焊过程中发生元素扩散,生成了金属间化合物,基体的整体性能有显著改善。随着材料中Cr、B、Si等合金元素含量的增加,喷焊时涂层中生成的BCr、Ni17Si3等共晶硬质相含量上升,促使涂层的显微硬度、耐磨性能等得到显著提升。其中,Ni60A涂层提升最为显著,其涂层硬度相当于基体硬度的2.5倍,耐磨性为基体的18.1倍。Ni25A涂层提升最小,其显微硬度是基体的1.3倍,耐磨性是基体的6.6倍。结论喷焊状态下的Ni60A涂层与基体冶金结合良好,涂层表面质量好,涂层性能最佳。 相似文献
9.
10.
11.
采用超音速火焰喷涂技术,在1Cr18Ni9Ti不锈钢基体表面制备NiCrWFeSiBCCo合金涂层. 采用金相显微镜(OM)、超景深体视显微镜(SM)、扫描电镜(SEM)观察涂层的显微组织和空蚀前后表面的微观形貌;采用表面粗糙度测试仪和显微硬度测试仪对涂层表面粗糙度和显微硬度进行表征;采用X-Ray衍射仪(XRD)分析涂层的相组成;采用磁致伸缩空蚀试验仪测定涂层的空蚀性能,并与1Cr18Ni9Ti不锈钢的空蚀性能进行比较. 结果表明,采用超音速火焰喷涂(HVOF)制备的NiCrWFeSiBCCo涂层组织均匀,结构致密(平均孔隙率为0.63%),硬度为1 004 HV,NiCrWFeSiBCCo涂层的抗空蚀性能明显优于1Cr18Ni9Ti不锈钢. 相似文献
12.
《稀有金属材料与工程》2012,(Z1):453-455
A Cr3C2-NiCr coating was prepared by high velocity oxy-fuel(HVOF)thermal spray on 1Cr18Ni9Ti stainless steel.Phases and microstructures of the coating were investigated by X-ray diffraction(XRD),optical microscopy(OM)and scanning election microscopy(SEM),respectively.The cavitation erosion resistance and silt erosion resistance of the coating were evaluated using a GB/T6383-2009 standard method in two experimental conditions(fresh water and water contained fine silt),compared with the coatings hydro machine material 1Cr18Ni9Ti stainless steel.The coating shows a layered structure and has a significantly higher microhardness(11.97 GPa)than that of the 1Cr18Ni9Ti stainless steel(2.1 GPa),which results in less mass losses both in cavitation erosion and silt erosion experiment.The HVOF coating has a predominant performance in the cavitation erosion and silt erosion resistance.The higher microhardness of the coating is the main cause which results in a less mass losses in the erosion experiments.And the mass loss usually happens at the edges of the pores. 相似文献
13.
采用HVOF技术在1Cr18Ni9Ti不锈钢基体上制备了Cr3C2/NiCr涂层,借助XRD,TEM,SEM等方法分析了涂层的组织形貌及相组成.以1Cr18Ni9Ti奥氏体不锈钢作为对比材料,用磁致伸缩空蚀仪配备扬沙装置测试了涂层在清水以及含沙水中抗空蚀性能.结果表明,涂层呈层状结构,含有未熔颗粒和少量孔隙,涂层由Cr3C2,Cr7C3,Cr23C6及NiCr等相组成;在清水试验中,1Cr18Ni9Ti不锈钢抗空蚀性能良好,与空蚀过程中1Cr18Ni9Ti奥氏体不锈钢产生加工硬化有直接关系;在含沙40 kg/m3试验水中,Cr3C2/NiCr涂层呈现出较好的抗空蚀性能,与涂层自身相组成以及较高硬度有关.Cr3C2/NiCr涂层破坏总是从孔隙等薄弱环节开始,而1Cr18Ni9Ti奥氏体不锈钢的破坏起始于晶界和孪晶界. 相似文献
14.
采用超音速火焰(HVOF)喷涂技术在1Cr18Ni9Ti不锈钢表面制备了Fe-Cr基涂层,用磁致伸缩汽蚀仪研究了喷涂层的汽蚀性,并与水利机械常用材料ZG06Cr13Ni5Mo马氏体不锈钢进行了对比。结果表明:涂层包含未熔或半熔的球形颗粒和少量孔隙,层与层之间结合紧密,层间无明显条带状组织。Fe-Cr涂层具有高的硬度(1099HV0.2),抗汽蚀性明显优于ZG06Cr13Ni5Mo马氏体不锈钢(285HV0.2)。两者的汽蚀形貌存在较大差异,ZG06Cr13Ni5Mo马氏体不锈钢的汽蚀坑圆滑,而Fe-Cr基涂层汽蚀坑形状极不规则,与涂层中的孔隙有某种对应关系。 相似文献
15.
1 Introduction Laser cladding is using high energy density laser beam to melt the cladding materials and makes them coagulate on the surface of the base materials. Laser cladding coating has high strength, good process property, high wear resistance, ero… 相似文献
16.
A WC–Co–Cr coating was deposited by a high velocity oxy-fuel thermal spray (HVOF) onto a 1Cr18Ni9Ti stainless steel substrate to increase its cavitation erosion resistance. After the HVOF process, it was revealed that the amorphous phase, nanocrystalline grains (Co–Cr) and several kinds of carbides, including Co3W3C, Co6W6C, WC, Cr23C6, and Cr3C2 were present in the coating. The hardness of the coating was improved to be 11.3 GPa, about 6 times higher than that of the stainless steel substrate, 1.8 GPa. Due to the presence of those new phases in the as-sprayed coating and its higher hardness, the cavitation erosion mass loss eroded for 30 h was only 64% that of the stainless steel substrate. The microstructural analysis of the coating after the cavitation erosion tests indicated that most of the corruptions took place at the interface between the un-melted or half-melted particles and the matrix (Co–Cr), the edge of the pores in the coating, and the boundary of the twin and the grain in the stainless steel 1Cr18Ni9Ti. 相似文献
17.
Zehua Wang Xuan Zhang Jiangbo Cheng Jinran Lin Zehua Zhou 《Journal of Thermal Spray Technology》2014,23(4):742-749
Two kinds of amorphous/nanocrystal coating (FeCrNiBSiNb and FeCrBSiWNb) were prepared by high-velocity arc spraying. The microhardness, bonding strength, and cavitation erosion resistance of the coatings were measured. The microstructure, amorphous content, and nanocrystal size were checked and the surface morphologies were investigated after cavitation erosion testing. The results indicated that both the FeCrNiBSiNb and FeCrBSiWNb coating consisted of amorphous/nanocrystal and Fe-based solid solution, with amorphous content of 73.6 and 57.2 vol.%, respectively. The Ni-Cr-Fe solid solution of the FeCrNiBSiNb coating had an average grain size of 19.8 nm, whereas the Fe-Cr solid solution of the FeCrBSiWNb coating had an average grain size of 29.4 nm. Moreover, both the FeCrNiBSiNb and FeCrBSiWNb coating exhibited good bonding strength, high hardness, and excellent cavitation erosion resistance. After 180 min of cavitation erosion, the cumulative weight loss of the FeCrNiBSiNb and FeCrBSiWNb coating was 21.3 and 24.0 mg, whereas the weight loss of a 0Cr18Ni9 coating was up to 62.6 mg. This investigation revealed that the cavitation damage to the thermally sprayed amorphous/nanocrystal coatings was mainly in the form of layer detachment, whereas for the conventional coating it took the form of particle breakage. 相似文献
18.
Ni-P涂层在泥浆中冲蚀-腐蚀行为研究 总被引:2,自引:0,他引:2
在浆料罐系统中研究了Ni-P涂层的泥浆冲蚀-腐蚀行为.Ni-P涂层抵抗泥浆冲蚀-腐蚀的能力大大高于马氏体不锈钢2Cr13和奥氏体不锈钢1Cr18Ni9Ti,扫描电镜分析表明,在线速度为6.2m/s时,2.5小时后Ni-P涂层表面轻微擦伤,在11.1m/s时,0.5小时后,表面为切削特征,运行不到15小时表面严重剥落。 相似文献
19.
清水和含沙水中20SiMn和0Cr13Ni5Mo钢的空蚀行为 总被引:4,自引:0,他引:4
利用超声振荡空蚀实验机对两种主要的水轮机用金属材料进行了清水和含水水条件下的空蚀行为研究,结果表明,高硬度的0Cr13Ni5Mo不锈钢抗清水和含水沙水的空蚀性能均显著高于低硬度的20SiMn低合金钢,在清水空蚀中0Cr13Ni5Mo不锈钢均匀脱落,而20SiMn低合金钢不均匀脱落,表面出明显的空蚀坑,空蚀和沙子冲蚀磨损的联合作用使得两种材料在含沙水中的空蚀失重显著高于水空蚀,0Cr13Ni5Mo不锈钢在含沙水中的空蚀育期显著缩短。 相似文献