钼铁对高锰钢自生碳化物组织与耐磨性的影响

通过在D256焊条药皮中加入一定量的钛铁、钒铁、钼铁、铬铁、碳化硼、石墨和稀土,利用焊接冶金反应在堆焊层中自生成硼化物、碳化物等硬质颗粒以提高耐磨堆焊材料的抗磨粒磨损性能.本文利用金相显微镜对堆焊层显微组织进行分析,通过硬度试验、磨损试验等,研究了焊条药皮组分中钼铁的加入对堆焊层硬度及耐磨性的影响.研究结果表明:加入钼铁后,堆焊层硬度和耐磨性都有所提高,其最高硬度达到60 HRC,比D256焊条提高了8HRC,耐磨性也提高了1倍.     

自生碳化物增强高锰钢堆焊材料的研究

通过在D256焊条药皮中加入钛铁、钒铁、石墨、稀土以及中碳锰铁,利用焊接冶金反应在高锰钢堆焊层中自发生成碳化物增强颗粒以提高其耐磨性,优化焊条药皮成分及配比,初步研制出具有优良耐磨性能的高锰钢自生硬质碳化物堆焊材料。研究结果表明:该耐磨堆焊材料的堆焊层组织为奥氏体组织和弥散分布于基体中的硬质碳化物颗粒,堆焊层硬度达到53HRC,耐磨性优于D256焊条,具有较高的耐磨性。     

自生碳化物高锰钢堆焊层的组织与力学性能

利用药皮中钛铁、钒铁、石墨、稀土等的高温电弧冶金反应在金属堆焊层中自发生成碳化物增强颗粒,以提高堆焊层耐磨性.利用扫描电镜和能谱仪,对金属堆焊层中碳化物颗粒的形貌、分布及成分进行了观察和分析,测量了金属堆焊层的硬度并进行了耐磨性试验.结果表明,随着药皮中钛铁、钒铁的增加,堆焊层硬度提高,当加入12wt%钛铁、12wt%钒铁时,堆焊层硬度为65 HRC,耐磨性最好.     

耐磨焊条中铁、石墨和碳化硼的优化设计

堆焊焊条设计试验采用L9（34）式正交表设计,以石墨、碳化硼和铁粉3个因素为变量,通过工艺性能定性分析,硬度值正交回归,最优化计算,得到优化试验配方和建立堆焊层金属硬度的回归方程,从而找到药皮主要成分石墨、碳化硼、铁粉对堆焊金属硬度、耐磨性等性能的影响规律.其中,碳化硼影响最大,铁粉次之,最小是石墨.随着碳化硼、铁粉、石墨增加硬度与耐磨性提高.铁粉量增加焊缝成型好,飞溅小.而石墨增加焊缝成型不好.碳化硼增加,飞溅加大.得到的最佳堆焊焊条配方,其焊接工艺性能优良,硬度值达68～71 HRC.     

含硼耐磨抗裂堆焊焊条的优化设计

采用正交试验方法优化设计出含硼耐磨抗裂堆焊焊条,通过硬度、金相组织、耐磨性、抗裂性等试验.分析堆焊层的显微组织结构.试验结果表明,该焊条堆焊层抗裂性高,焊前不预热,焊后不缓冷,连续堆焊不产生裂纹;耐磨性好,相对耐磨性优于D667焊条.     

自生碳化物对高锰钢堆焊层组织和性能的影响

在D256焊条药皮中加入钒铁、石墨、稀土等,利用焊接电弧冶金反应自发生成碳化物增强颗粒.实验结果表明:堆焊层组织为奥氏体组织和弥散分布于基体中的硬质碳化物颗粒,硬度达到64 HRC,其耐磨性为D256焊条堆焊层的4倍.     

高效高硬度低成本耐磨堆焊焊条的研制

研制了一种新型的高效高硬度低成本耐磨堆焊焊条.焊条中大量加入铁粉和适量的石墨而不加任何矿石粉,少加或不加价贵组分,系统调整焊条药皮配方以及筛选合适的合金组元,既提高了焊条的综合性能又降低了成本.结果表明,焊条的工艺性能良好,焊条的熔化效率达3kg/h,熔敷效率达226.9%,焊条收得率达80%,堆焊单层熔敷金属硬度达67 HRC,耐磨性为某高铬铸铁焊条的1.52倍,同时具有较好的抗裂性.     

新型双熔敷极TiC-VC增强耐磨堆焊组织与性能

采用钛铁、钒铁和石墨等原材料,首次利用新颖的双熔敷极焊条电弧焊,合成TiC-VC超硬质颗粒增强Fe基堆焊层.利用X射线衍射、扫描电镜、耐磨性试验分析了堆焊层的组织与耐磨性能.结果表明,双熔敷极焊条电弧焊条件下,其特殊的电弧结构使得Ti元素主要起脱氧剂的作用,用于形成碳化物的很少,堆焊层中仅有少量TiC形成.堆焊层主要以...     

抗裂性耐磨性兼具的堆焊焊条的研究

在分析堆焊条抗裂与耐磨性关系的基础上,采用廉价钛铁、钡铁和人造金红石、石墨等材料作为焊条药成分,以Ｈ０８Ａ为焊芯,通过电弧冶金反应获得含ＴｉＣ－ＶＣ超硬质相的堆焊层,极大地提高了堆焊层的硬度和耐磨性,弥散分布的硬化物超硬质相质点配合低碳马氏基体及少量残余工体使堆焊层具有良好的抗裂性。抗裂耐磨及其经济性使该焊条在耐磨粒磨损和冲击工况下具有广泛的应用前景。     

EDC68高硬度高耐磨堆焊电焊条

采用ZWZY5配方设计系统拟订试验方案,对试验数据进行直观分析,正交回归计算,建立了堆焊金属硬度的回归方程,并得到堆焊焊道裂缝数量直观分析结果,从而找出了各药皮成分对堆焊金属硬度、抗裂性等性能的影响规律,然后以堆焊金属硬度的回归方程作为目标函数,进行最优化计算,求得堆焊金属硬度最高的堆焊焊条配方,再根据焊道裂缝数量的直观分析及工艺性能情况,综合考虑药皮成分对抗裂性能和工艺性能的影响。对该焊条配方稍做适当调整,最后确定了EDC68堆焊电焊条配方。EDC68堆焊电焊条可进行不预热或低温预热（150-350℃）堆焊,其堆焊层不开裂或轻微开裂,堆焊金属具有高硬度、高耐磨、高韧性、耐冲击等优良综合性能,其常温硬度达68-71HRC,且能适应冲击工况要求。     

Development of new type of wear and crack resistant hardfacing electrode

By using H08A bare electrode and the coating fluxes of ferrotitanium, rutile, graphite, calcium carbonate and calcium fluoride, a new type of wear and crack resistant hardfacing electrode was developed. The microstructure and wear properties of deposited layer were studied by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffractometry(XRD) and wear test. The results indicate that TiC particles are produced by direct metallurgical reaction between ferrotitanium or rutile and graphite during welding process. TiC particles with sizes in the range of 3 - 5μm are dispersed in the matrix of lath martensite and retained austenite. The deposited layer of the new type of hardfacing electrode possesses better wear and crack resistance than that of D618 and D667 hardfacing electrodes.     

抗冲击磨损奥氏体堆焊材料

针对具有冲击磨粒磨损工况条件，成功研制出了一种奥氏体堆焊材料EKCM50。该堆焊材料为Fe-Mn-Cr-Mo-V合金系，通过耐磨性对比试验分析，堆焊合金耐磨性能优于D256焊接材料。经过加工硬化冲击试验，EKCM50焊接材料堆焊层硬度由32HRC升高到45HRC，经过冲击磨损试验，40min后，试验材料堆焊磨损失重几乎不变。通过对该材料的加工硬化和磨损性能的试验研究，探讨了此种奥氏体材料的加工硬化及耐磨机理，以及加入的合金元素对该焊接材料的耐磨性及耐磨机理的影响规律。     

Microstructures and properties of non-preheated hardfacing welding

A new type of non-preheated hardfacing electrode was developed using H08A as the core and the coat contents including ferrotitaninm, ferrovanadium, graphite, rutile etc. The microstrnctures and properties of hardfacing metal were systematically researched. The results show the hardness of hardfacing metal increases with increasing of ferrotitanium, ferrovanadium, graphite in the coat, but the crack resistance and processing weldability become worse. The carbides formed by arc metallurgic reaction are uniformly dispersed in the matrix structure. The phases of hardfacing metal consist of α-Fe, γ-Fe, VC, TiC and Fe3 C.The carbides are compression aggregation of TiC and VC, and their appearances present irregular block. The matrix microstrncture of hardfacing metal is lath martensite. The hardfacing layers with better crack resistance and wearability are achieved and no visible cracks occur when using non-preheated electrode in continuous welding process. Hardness of hardfacing metal is more than 60HRC, and its relative wearability is five times of wearability of D667 electrode in abrasive wear test.     

纳米大理石对D600R堆焊焊条性能的影响

用粒径70～90nm大理石取代堆焊焊条D600R药皮中的微米大理石,制成纳米大理石焊条.利用汉诺威电弧质量分析仪对焊接过程中的电流电压和短路时间进行测试,获得微米大理石焊条和纳米大理石焊条的燃弧特征;通过焊接工艺试验、测氢试验、熔化温度测试、硬度试验、耐磨试验和微观分析,分别对两种焊条的工艺性能和力学性能进行分析.结果表明,用纳米大理石替代微米大理石可降低焊条药皮的熔化温度和堆焊层金属中的扩散氢含量;提高焊条的熔敷效率;降低焊条短路电压、短路电流概率密度和,在短路时间t12.05ms时间段内缩短累计短路时间;改善焊条操作性能;提高堆焊层金属硬度和耐磨性.     

Study on Mn-Si-B system hardfacing electrode

ＳｔｕｄｙｏｎＭｎ－Ｓｉ－ＢｓｙｓｔｅｍｈａｒｄｆａｃｉｎｇｅｌｅｃｔｒｏｄｅＷａｎｇＬｉａｎｆａｎｇ；ＣｈｅｎＢｏｌｔａｎｄＪｉｎＸｉｌｏｎｇ（ＴｓｉｎｇｈｕａＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ）Ａｂｓｔｒａｃｔ：Ｍｎ－Ｓｉ－Ｂｓｙｓｔｅｍｍｅｄ...     

Fe-Mn-Cr-Mo-V系抗冲击磨料磨损堆焊材料

采用H08A焊芯,研制的TKCE50焊条与传统的高锰钢焊条D256进行对比分析,通过冲击磨损试验,硬度测试及金相显微分析,系统研究了堆焊层的硬度、耐磨性、抗冲击后的加工硬化程度以及各种合金元素对堆焊层性能的影响规律.结果表明,所研制的Fe-Mn-Cr-Mo-V系堆焊焊条具有较高的韧性、抗裂性及优异的加工硬化性能,抗冲击磨料磨损性能十分突出;随着Cr,Mo,V元素含量的增加,堆焊层金属端面硬度增加,达到一定值后,其增加变缓.冲击9 000次后,加工硬化达到极限,此时的堆焊层金属磨损失重最小,耐磨性最好.     

球墨铸铁轧辊电火花沉积层组织结构和性能

采用电火花沉积方法将YG8电极材料沉积在球墨铸铁轧辊材料上,制备了WC沉积涂层,研究了其微观组织及耐磨性能.结果表明:沉积层主要由Fe_3W_3C、Co_3W_3C、W_2C和Fe_7W_6等相组成,沉积层与基体呈冶金结合,Fe_7W_6、W_2C等硬质相弥散分布于沉积层中,部分区域硬质相达到了纳米颗粒尺寸;沉积层硬度分布不均匀,平均硬度为1759 HV0.3;沉积层具有优异的耐磨性,其磨损性能是基体的3.7倍;沉积层的磨损机理以粘着磨损和疲劳磨损为主,细小的弥散分布的硬质相是沉积层硬度以及耐磨性提高的主要因素.     

Fabrication of multiple carbide particles reinforced Fe-based surface hardfacing layer produced by gas tungsten arc welding process

In this paper, a multiple carbide particle reinforced Fe-based surface coating has been in situ synthesized by gas tungsten arc welding (GTAW) melting a precursor mixture of graphite, ferrotitanium (Fe-Ti) and ferrovanadium (Fe-V) alloy powders on AISI 1020 steel substrate. The microstructure and wear properties of the Fe-based surface hardfacing layers were investigated by means of a scanning electron microanalysis (SEM), X-ray diffractometer (XRD) and wear tester. The results showed that (Ti,V)C multiple carbide particle and TiC carbide particle can be synthesized via reaction of Fe-Ti, Fe-V and graphite during GTAW melting process. The selection area diffraction pattern (SADP) analysis indicated that (Ti,V)C crystallizes with the cubic structure, which indicates that (Ti,V)C carbides were multiple carbides with V dissolved in the TiC structure. The Fe-based surface hardfacing layer reinforced by multiple carbides gave an excellent wear resistance and appeared a mild wear with fine scratches.     

A flux-core wire for hardfacing sealing surfaces of stop valves

A new flux-cored wire producing the deposited metal of high-chromium steel of the Fe–Cr–Ni–Mo–Mn–Si–Nb–Ti–B alloying system is described. The structure of the deposited metal and the composition of the hardening phases are determined. The role of borides in increasing the wear resistance and stability of the properties of the metal in hardfacing is analysed.     

大型冷冲模铸铁镶块堆焊焊条的研制及应用

确定了适合于大型冷冲模镶块刃口堆焊的焊条的合金成分．并给出了其比较合理的焊芯和药皮化学成分；测试了新焊条堆焊层金属的化学成分、硬度、硬度梯度、金相组织，其结果均满足在铸铁基体上堆焊制造冷冲模镶块的要求．具有良好的焊接工艺性能。与常用冷冲模堆焊焊条D322相比．在相同条件下，新型焊条的耐磨性能优于D322。