选择性激光熔覆钴铬合金与瓷的结合性能研究

目的:评价选择性激光熔覆(selective laser melting,SLM)技术制作的钴铬合金与瓷粉的结合强度。方法:根据YY 0621-2008标准采用三点弯曲法测试比较SLM和传统失蜡铸造法的钴铬合金的金瓷结合强度,采用Vita瓷粉和Noritake瓷粉,对金瓷界面进行扫描电镜观察。结果:无论Vita瓷粉或Noritake瓷粉,SLM制作法的钴铬合金的金瓷结合强度均大于传统铸造法的金瓷结合强度(P<0.05)。SEM检测显示SLM钴铬合金的金瓷渗透深度均大于传统铸造钴铬合金的金瓷渗透深度。结论:SLM钴铬合金的金瓷结合强度大于YY0621-2008标准(25 MPa),也大于传统失蜡铸造法所获得的金瓷结合强度。     

制作方法对钴铬合金金瓷结合性能的影响

目的 比较铸造钴铬合金与选区激光熔化（SLM）钴铬合金金瓷结合强度的差异。方法 用铸造法和SLM技术制作钴铬合金试件各10个,在中间1/3区域熔附瓷粉,采用剪切力试验测试金瓷结合强度并观察断裂类型。采用SPSS 13.0软件中的t检验对结果进行统计学分析。结果铸造组、SLM组剪切力分别为（33.11±4.98）、（30.94±5.98） MPa,二者间差异无统计学意义（P>0.05）。样本的断裂类型为复合断裂。结论 SLM钴铬合金修复体精密度较高,其金瓷结合强度与铸造钴铬合金相近。     

反复烧结对选择性激光熔积钴铬合金硬度的影响

目的：探讨反复烧结对选择性激光熔积技术（SLM）制作的钴铬合金硬度的影响。方法用具有相同成分的钴铬合金粉末和金属块,分别运用SLM 技术（SLM 组）和铸造工艺（铸造组）制作,每组各制作25个圆柱形试件（10mm 直径*3mm 厚度）,随机分成A、B、C、D、E 组进行烧结,其中A 组不烧结,B、C、D、E 组分别烧结1、3、5、7次,在显微硬度仪上分别测量其维氏硬度,比较SLM 组和铸造组的硬度。结果烧结0、1、3、5、7次后,SLM 组的平均维氏硬度分别为427.9、571.3、600.4、620.9、673.3HV,铸造组的平均维氏硬度分别为354.7、374.7、429.3、440.4、449.1HV,相同烧结次数的 SLM 组和铸造组之间比较,其差异具有统计学意义（P<0.05）。结论烧结能增加钴铬合金的硬度,SLM 钴铬合金比铸造钴铬合金硬度增加更明显;烧结前后,SLM 钴铬合金均较铸造钴铬合金硬度高。     

激光表面强化技术对牙科钴铬合金机械性能影响的研究

目的：研究激光表面强化技术对牙科钴铬合金机械性能的影响。方法：选用临床上常用的钴铬合金作为实验对象,并制成检测试件,进行激光表面强化处理,扫描电镜观察合金表面金相结构及形貌的变化;并测试试件表面硬度及耐磨性的改变,结果进行统计学分析。结果：激光表面强化后,合金晶粒得到细化;表面硬度及耐磨性得到提高（P〈0.01）。结论：激光表面强化技术有明显改善牙科钴铬合金机械性能的作用。     

选择性激光熔积技术制作钴铬合金基底冠的边缘密合度研究

目的 研究选择性激光熔积(selective laser melting,SLM)制作的钴铬合金基底冠的边缘密合度.方法 分别采用SLM技术和传统铸造法,各制作20个钴铬合金基底冠,用硅橡胶复制其边缘间隙宽度,在体式显微镜下观察其边缘密合度并加以比较.结果 SLM技术制作的钴铬合金基底冠的边缘间隙宽度平均值为49.6μm,显著小于铸造组的90.8μm (P＜0.05);结论 SLM技术制作的钴铬合金基底冠的边缘密合度优于传统铸造组,具有临床应用前景.     

选择性激光熔积钴铬合金在含氟口腔环境中电化学腐蚀性能的研究

目的 考量采用区域选择性激光熔化(SLM)技术制作的钴铬合金口腔修复材料在含氟口腔环境中的耐腐蚀性能.方法 选取具有相同成分的Co-Cr合金金属粉末和金属块,分别运用SLM技术(SLM组)和传统的铸造工艺(对照组)各制作5个试件(圆柱形,直径10 mm,厚度3 mm),在模拟含氟口腔环境下(pH值6.8,NaF 0.1％),采用电化学交流阻抗谱(EIS)的方法,分析两组试件的耐腐蚀性能.结果 对照组和SLM组的表面氧化层电阻(Rp)值分别为3.28±1.53和6.69±3.30,组间比较差异无统计学意义(P＞0.05).结论 在模拟含氟口腔环境中,SLM技术制作的钴铬合金与传统铸造方式加工的钴铬合金具有相似的耐腐蚀性能,能够满足临床要求.     

铸造和切削钴铬合金与瓷结合强度的比较

目的比较铸造和切削钴铬合金与瓷的结合强度。 方法分别使用失蜡铸造法和计算机数字控制切削法制作钴铬合金试件（25 mm × 3 mm × 0.5 mm）,在试件表面中心区域熔附8 mm × 3 mm × 1.1 mm的瓷,使用ISO 9693规定的三点弯曲测试对金瓷试件进行金瓷结合强度测定。使用佩有X线能谱分析的扫描电镜观察试件的显微特征,元素扩散以及开裂试件开裂模式、残留瓷面积分数。结合强度、残留瓷面积分数数据使用独立样本t检验进行统计学分析（α=0.05）。 结果铸造钴铬合金与瓷的结合强度为（31.46 ± 3.61）MPa,切削钴铬合金与瓷的结合强度为（31.74 ± 3.33）MPa,两组间差异没有统计学意义（t=-0.204,P= 0.738）,三点弯曲测试后,铸造组和切削组所有开裂试件都为混合开裂模式,铸造组和切削组的残留瓷面积分数分别为0.32 ± 0.06和0.45 ± 0.08,两组间差异有统计学意义（t=-4.67,P<0.001）,切削组合金表面比铸造组有更多的瓷残留。 结论铸造法和切削法制作的钴铬合金金瓷结合强度没有差异。     

氟离子对两种不同工艺制作的钴铬合金耐腐蚀性能的影响

目的 在模拟口腔环境下研究氟离子对采用选择性激光熔覆（SLM）技术和传统铸造技术两种工艺制作的钴铬合金耐腐蚀性的影响。方法 选择具有相同材料成分的钴铬合金金属粉末和金属块,分别采用SLM（SLM组）和铸造技术（Cast组）各制作15个试件,置于含不同氟离子质量分数（0、0.05%、0.20%）的酸性人工唾液（pH值为5.0）中浸泡24 h进行电化学试验,采用动电位极化曲线法测试合金的自腐蚀电位Ecorr、自腐蚀电流密度Icorr和极化电阻Rp,同时结合扫描电子显微镜（SEM）观察,分析两组试件的耐腐蚀性能。结果 铸造工艺制作的钴铬合金在酸性人工唾液中的Ecorr随着氟离子质量分数的升高而减小。当氟离子质量分数为0.20%时,两种工艺制作的钴铬合金的Ecorr、Icorr、Rp均有明显改变（P<0.05）,SEM结果也显示合金表面均出现腐蚀现象。当氟离子质量分数为0.20%时,Cast组钴铬合金的Icorr高于SLM组,而Ecorr和Rp低于SLM组（P<0.05）。结论 氟离子可降低两种工艺制作的钴铬合金的耐腐蚀性,在氟离子质量分数较高（0.20%）时,SLM技术制作的钴铬合金的耐腐蚀性优于铸造工艺制作的钴铬合金。     

氮化钛镀膜对钴铬合金机械及化学性能的影响

目的研究氮化钛镀膜对牙科铸造用钴铬合金机械及化学性能的影响,为氧化钛镀膜在可摘局部义齿钴铬合金铸造支架的临床应用提供依据。方法制作钴铬合金试件79个,随机分为未镀膜组（42个）和镀膜组（37个）,镀膜组的试件采用热阴极离子镀膜技术在其表面沉积氮化钛膜。扫描电镜观察试件表面形貌;X射线衍射仪对镀膜进行物相分析;X射线荧光镀层厚度测量仪测量镀膜的厚度;划痕法测量TiN镀膜与钴铬合金基材的结合力。维氏硬度计、摩擦磨损仪和人工唾液浸泡法测量所有试件硬度、摩擦系数、耐磨性、耐腐性以及金属离子析出量。所得数据进行t检验。结果氮化钛镀膜的钴铬合金试件,硬度有所提高,摩擦系数减小,同等磨损实验条件下,镀膜组试件的磨损失重量仅为未镀膜组的1/16。试件的腐蚀电位平均值,镀膜组为-0.2453V,未镀膜组为-0.1400V（P〈0.05）。随着浸泡时间的延长,镀膜组试件析出的金属离子总量及各类离子的浓度均较低,析出离子量轻微增加;未镀膜组试件析出的各类金属离子量（铬除外）明显增加（P〈0.001）。结论氮化钛镀膜能够明显改善牙科铸造用钴铬合金的机械、化学性能。     

选择性激光熔化钴铬合金基底冠与铸造钴铬合金基底冠边缘适合性比较

目的评价选择性激光熔化钴铬合金烤瓷冠和传统铸造钴铬合金烤瓷冠的边缘适合性。方法制作下颌第一磨牙全冠牙体制备标准金属代型1个,复制并灌注石膏模型后,制作选择性激光熔化钴铬合金基底冠和铸造钴铬合金基底冠各10个,依次将其就位于金属标准代型上。在体式显微镜下,对基底冠边缘与金属代型肩台之间的适合度进行观察,用CCD数字图像捕捉系统进行成像,并用专业测量软件测量边缘缝隙宽度。最后计算各组10个样本的平均值,采用SPSS 20.0软件包对数据进行统计学处理。结果选择性激光熔化钴铬合金基底冠和传统铸造钴铬合金基底冠平均边缘缝隙宽度分别为(48.20±4.61)μm、(77.90±6.26)μm,选择性激光熔化钴铬合金基底冠边缘缝隙宽度显著小于传统铸造钴铬合金基底冠(P<0.01)。结论 2种瓷熔附金属基底冠的边缘适合度均在临床可接受范围内,而选择性激光熔化钴铬合金基底冠边缘适合度显著高于传统铸造钴铬合金基底冠。     

Comparison of the bond strength of laser-sintered and cast base metal dental alloys to porcelain

OBJECTIVE: The purpose of this study was to compare shear bond strengths of cast Ni-Cr and Co-Cr alloys and the laser-sintered Co-Cr alloy to dental porcelain. METHODS: Dental porcelain was applied on two cast and one laser-sintered base metal alloy. Ten specimens were prepared for each group for bond strength comparison. ANOVA followed by Tukey HSD multiple comparison test (alpha=0.05) was used for statistical analysis. Fractured specimens were observed with a stereomicroscope to classify the type of failure after shear bond testing. RESULTS: While the mean shear bond strength was highest for the cast Ni-Cr metal-ceramic specimens (81.6+/-14.6MPa), the bond strength was not significantly different (P>0.05) from that for the cast Co-Cr metal-ceramic specimens (72.9+/-14.3MPa) and the laser-sintered Co-Cr metal-ceramic specimens (67.0+/-14.9MPa). All metal-ceramic specimens prepared from cast Ni-Cr and Co-Cr alloys exhibit a mixed mode of cohesive and adhesive failure, whereas five of the metal-ceramic specimens prepared from the laser-sintered Co-Cr alloy exhibited the mixed failure mode and five specimens exhibited adhesive failure in the porcelain. CONCLUSIONS: The new laser-sintering technique for Co-Cr alloy appears promising for dental applications, but additional studies of properties of the laser-sintered alloy and fit of castings prepared by this new technique are needed before its acceptance into dental laboratory practice. SIGNIFICANCE: Laser sintering of Co-Cr alloy seems to be an alternative technique to conventional casting of dental alloys for porcelain fused to metal restorations.     

Corrosion behaviour and surface analysis of a Co-Cr and two Ni-Cr dental alloys before and after simulated porcelain firing

This study evaluated the corrosion behaviour and surface properties of a commercial cobalt-chromium (Co-Cr) alloy and two nickel-chromium (Ni-Cr) alloys [beryllium (Be)-free and Be-containing] before and after a simulated porcelain-firing process. Before porcelain firing, the microstructure, surface composition and hardness, electrochemical corrosion properties, and metal-ion release of as-cast alloy specimens were examined. After firing, similar alloy specimens were examined for the same properties. In both as-cast and fired conditions, the Co-Cr alloy (Wirobond C) showed significantly more resistance to corrosion than the two Ni-Cr alloys. After firing, the corrosion rate of the Be-free Ni-Cr alloy (Stellite N9) increased significantly, which corresponded to a reduction in the levels of Cr, molybdenum (Mo), and Ni in the surface oxides and to a reduction in the thickness of the surface oxide film. The corrosion properties of the Co-Cr alloy and the Be-containing Ni-Cr alloy (ChangPing) were not significantly affected by the firing process. Porcelain firing also changed the microstructure and microhardness values of the alloys, and there were increases in the release of Co and Ni ions, especially for Ni from the Be-free Ni-Cr alloy. Thus, the corrosion rate of the Be-free Ni-Cr alloy increased significantly after porcelain firing, whereas the firing process had little effect on the corrosion susceptibility of the Co-Cr alloy and the Be-containing Ni-Cr alloy.     

激光选区熔化成形钴铬合金及钛合金金瓷结合强度的研究

目的　比较激光选区熔化（selective laser melting,SLM）技术与传统方法制作的钴铬合金（Co-Cr）和钛合金（Ti6Al4V）在金瓷结合性能方面的差异。方法　分别采用传统方法（铸造法和锻造法）和SLM技术制作4组直径10 mm、厚1 mm的圆形片状试件,每组各10个,分别记为铸造Co-Cr（CC）组、锻造Ti6Al4V（DT）组、SLM Co-Cr（SC）组、SLM Ti6Al4V（ST）组。流水下打磨抛光试件,氧化铝喷砂剂喷砂后,激光扫描共聚焦显微镜（CLSM）检测试件表面粗糙度。室温下干燥后分别烧结瓷粉,采用剪切强度测试法测定各组的金瓷结合强度,并进行统计学分析。体视显微镜观察瓷层断裂模式。场发射扫描电镜（FE-SEM）对金瓷结合界面形貌进行分析。结果　各组试件表面粗糙度未见明显差异（P > 0.05）。CC组和SC组的剪切强度无明显差异,分别为（25.949 ± 2.708）MPa和（26.707 ± 1.559）MPa,均显著高于DT组［（18.259 ± 1.882）MPa］和ST组［（21.504 ± 3.019）MPa］（P < 0.05）,其中DT组低于ST组（P < 0.05）。各组剪切强度测试后金瓷断裂模式均为混合断裂。FE-SEM下观察显示SC组和CC组金瓷界面结合紧密,DT组和ST组金瓷界面偶见气孔和裂隙。结论　SLM技术制作的Co-Cr金瓷结合强度与传统铸造法相当,SLM技术制作的Ti6Al4V金瓷结合强度明显高于传统锻造法。SLM技术作为一种新型的激光3D打印技术,在口腔修复学领域有极大的应用潜力。     

Metallurgical, surface, and corrosion analysis of Ni-Cr dental casting alloys before and after porcelain firing.

OBJECTIVES: A porcelain veneer is often fired on nickel-chromium casting alloys used in dental restorations for aesthetic purposes. The porcelain-fused-to-metal (PFM) process brings the temperature to over 950 degrees C and may change the alloy's corrosion properties. In this study, the metallurgical, surface, and corrosion properties of two Ni-Cr alloys were examined, before and after PFM firing. METHODS: Two types of alloy were tested-a high Cr, Mo alloy without Be and a low Cr, Mo alloy with Be. Before the PFM firing, specimens from both alloys were examined for their microstructures, hardness, electrochemical corrosion properties, surface composition, and metal ion release. After the PFM firing, the same specimens were again examined for the same properties. RESULTS: Neither of the alloys showed any differences in their electrochemical corrosion properties after the PFM firing. However, both alloys exhibited new phases in their microstructure and significant changes in hardness after firing. In addition, there was a slight increase in CrO(x) on the surface of the Be-free alloy and increased Mo-Ni was observed on the surface of both alloys via X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). This might be one of the reasons why both alloys had increased Ni and Mo ion release after firing. SIGNIFICANCE: The PFM firing process changed the alloys' hardness, microstructure, and surface composition. No significant changes in the alloys' corrosion behavior were observed, however, the significant increase in metal ion release over a month may need to be further investigated for its clinical effects.     

�����Ͻ����ܸ��Ͻ�Ļ�е���ܼ���ɽ��ǿ�ȱȽ��о�

目的 对比钯银(Pd-Ag)合金和钴铬(Co-Cr)合金的机械性能及金瓷结合强度,为临床提供基础数据.方法 本研究于2010年12月至2011年2月在中国科学院金属研究所分析测试部完成.常规方法制作Pd-Ag合金和Co-Cr合金试件,首先对二者进行硬度测试和拉伸测试,然后分别行常规烤瓷并利用水平剪切法进行界面结合强度测试,利用扫描电镜(SEM)和能谱分析技术对金瓷界面进行观察和元素分析.结果 硬度:Pd-Ag合金为(187.44±3.64) HV,低于Co-Cr合金(361.53±10.15)HV(P＜ 0.05).拉伸测试:Pd-Ag合金的屈服强度为(467.50±14.40)MPa,小于Co-Cr合金(568.10± 30.94) MPa (P＜ 0.05);Pd-Ag合金的抗拉强度为(631.83±15.51)MPa,小于Co-Cr合金(758.73±25.85) MPa(P＜ 0.05).剪切强度:Pd-Ag合金为(57.67±5.44) MPa,Co-Cr合金为(26.80±4.95)MPa,差异有统计学意义(P＜0.05).扫描电镜观察和能谱分析显示:2种合金与瓷之间均存在过渡层,合金与瓷层间存在元素的相互渗透.结论Pd-Ag合金的机械性能低于Co-Cr合金,但可满足临床需要;而Pd-Ag合金的金瓷结合强度高于Co-Cr合金.     

Metallurgical Structure and Microhardness of Four New Palladium-Based Alloys

Purpose This investigation compared the Vickers hardness and microstructures of four recently marketed, palladium-based alloys for metal-ceramic restorations. Materials and Methods Wax patterns simulating copings for maxillary central incisors were invested in a fine-grained, carbon-free, phosphate-bonded investment. Following burnout, the palladium alloys were fused with a gas-oxygen torch, centrifugally cast, and bench-cooled. Representative castings were embedded in transparent metallographic resin and sectioned to yield two mirror-image specimens. The specimens were evaluated in either the as-cast condition or following heat treatment simulating the firing cycles for Vita VMK porcelain. Vickers hardness measurements (n = 50) were made using a 1-kg load, and photomicrographs of polished and etched specimens were obtained with a scanning electron microscope. Results The measured values of microhardness for the as-cast alloys were in excellent agreement with values reported by the manufacturer. The hardness in the as-cast condition was significantly greater for the Pd-Cu-Ga-In alloy, compared with the other three alloys, which did not contain copper. For the three high-palladium (≥ 75 wt%) alloys, there were small (4%-8%) decreases in hardness following heat treatment, whereas a larger decrease (13%) in hardness occurred for the Pd-Ag-In-Sn alloy after heat treatment. The porcelain firing cycles caused microstructural homogenization for all four alloys, and the relatively thick near-surface oxidation region in the Pd-Cu-Ga-In and Pd-Ag-In-Sn alloys was not observed in the two heat-treated Pd-Ga-Ag-In-Au alloys. Conclusions The multiphasic microstructures of these alloys may have some significance for the in vitro and clinical corrosion behavior and the metal-ceramic bond strength. The hardness for the three high-palladium alloys may be controlled by submicroscopic precipitates that remain unaltered by heat treatment. The significantly greater hardness for the Pd-Cu-Ga-In alloy may cause greater difficulty for finishing castings in the dental laboratory compared with the other three alloys studied. The strengthening mechanism for the Pd-Ag-In-Sn alloy has significant temperature dependence, which might be exploited to achieve optimum mechanical properties.     

三种口腔铸造合金耐蚀性及表面氧化膜的比较

目的 探讨3种常用口腔铸造合金模拟烤瓷前后的耐蚀性差异及氧化膜成分,以期为临床合理选择非贵金属合金提供依据.方法 用电感耦合等离子体原子发射光谱法(inductively coupled plasma atomic emission spectroscopy,ICP-AES)检测模拟烤瓷前后3种常用烤瓷非贵金属合金(镍铬合金、钴铬合金、镍钛合金)在达尔伯克改良伊格尔培养液中浸泡30 d后离子析出的种类和含量.同时用X射线光电子能谱(X-ray photoelectron spectroscopy,XPS)对模拟烤瓷后合金表面生成的氧化膜进行分析,扫描电镜(SEM)对合金表面腐蚀形态进行观察.结果 模拟烤瓷前3种合金离子总质量浓度由大到小依次为镍铬合金[(2.829±0.694)mg/L]、钴铬合金[(2.120±0.418)mg/L]、镍钛合金[(1.211±0.101)mg/L];镍铬合金组镍的质量浓度[(1.531±0.392)mg/L]＞镍钛合金组[(0.830±0.052)mg/L],钴和钼离子质量浓度由大到小为钴铬合金组[钴:(0.048±0.011)mg/L;钼:(1.562±0.333)mg/L]、镍铬合金组[钴:(0.034±0.002)mg/L;钼:(1.264±0.302)mg/L]、镍钛合金组[钴:(0.013±0.006)mg/L;钼:(0.151±0.026)mg/L],差异有统计学意义(P＜0.05).模拟烤瓷后3种合金离子析出总量[镍铬合金:(0.861±0.054)mg/L;钴铬合金:(0.695±0.327)mg/L;镍钛合金:(0.892±0.115)mg/L]均比未模拟烤瓷处理的合金离子析出总量少,差异有统计学意义(P＜0.05).XPS分析显示,模拟烤瓷后3种合金表面Cr2O3和钼、镍氧化物的含量增加.结论 3种常用烤瓷铸造合金中镍铬合金的离子析出量最大,耐蚀性最差;烤瓷加热处理可促进这3种合金生成连续的Cr2O3氧化膜,使合金的耐蚀性增强.

Abstract：

Objective To evaluate the types and compositions of oxide films formed during porcelain-fused-to-metal( PFM ) firing on three kinds of dental casting alloys, and to investigate the corrosion property of these alloys in Dulbecco's modification of Eagle's medium( DMEM ) cell culture fluid, before and after PFM firing. Methods Specimens of three dental casting alloys( Ni-Cr, Co-Cr and Ni-Ti) before and after PFM firing were prepared, and were immersed in DMEM cell culture fluid. After 30 days, the type and concentration of released metal ions were measured using inductively coupled plasma atomic emission spectroscopy(ICP-AES). X-ray photoelectron spectroscopy(XPS) and scanning electron microscope( SEM )were used for analysis of oxide film on the alloys. One way-ANOVA was adopted in data analysis. Results The total amount of metal ions released from the three dental alloys was found to be highest in Ni-Cr alloy [(2.829±0.694) mg/L], followed by Co-Cr[(2. 120 ±0.418) mg/L]and Ni-Ti alloy[(1.211 ±0. 101 ) mg/L]. The amount of Ni ions released from Ni-Cr alloys[( 1. 531 ± 0. 392) mg/L]was higher than that from Ni-Ti alloys[(0. 830 ±0. 052) mg/L]. The amount of Cr, Mo ions released from Co-Cr alloy [Cr: (0. 048 ± 0. 011 ) mg/L, Mo: ( 1. 562 ± 0. 333 ) mg/L]was higher than that from Ni-Cr alloy[Cr:(0. 034 ±0. 002) mg/L, Mo: ( 1. 264 ±0. 302) mg/L]and Ni-Ti alloy[Cr: (0. 013 ±0. 006) mg/L, Mo:(0. 151 ±0. 026) mg/L](P ＜0. 05). After PFM firing, the total amount of metal irons released from the three dental alloys decreased[N i-Cr: (0. 861 ± 0. 054 ) mg/L, Co-Cr: (0. 695 ± 0. 327 ) mg/L, Ni-Ti:(0. 892 ±0. 115) mg/L](P ＜ 0. 05). In addition, XPS showed increase of Cr2O3 and Mo-Ni oxide on the surface of all the alloys after PFM firing. Conclusions The amount of ions released from Ni-Cr alloy was the highest among the three dental casting alloys, this means Ni-Cr alloy is prone to corrode. The PFM firing process changed the alloys' surface composition. Increased Ni, Cr and Mo were found in oxide film, and the increase in Cr2O3 can improve the corrosion-resistance of alloys.     

3种烤瓷铸造合金的离子析出研究

目的 研究3种常用烤瓷非贵金属合金模拟烤瓷前、后在体外细胞培养液中离子析出的量及种类。方法 用失蜡法铸造3种常用烤瓷非贵金属合金试件,镍铬合金、钴铬合金、镍钛合金,置于DMEM体外细胞培养液中30 d后重新打磨,模拟烤瓷加热过程,之后放回DMEM体外细胞培养液中浸泡30 d,用电感耦合等离子发射光谱法(ICP-AES)观察烤瓷处理前、后3种合金离子的析出的改变,扫描电镜(SEM)对表面形态观察。结果 (1)3种合金离子析出总量依次为镍铬合金>钴铬合金>镍钛合金,(2)模拟烤瓷程序后3种合金离子析出总量减少,差异具有统计学意义(P<0.05)。结论 3种常用烤瓷非贵金属合金中,镍铬合金的离子析出量最大,生物相容性最差;烤瓷过程会促进这3种合金表面氧化膜的生成,使合金的耐腐蚀性有所增强。