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中间合金粉对激光选区熔化TMZF合金电化学性能的影响

  • 褚清坤1,2

    机 构：

    1. 广东工业大学 材料与能源学院, 广州 510006

    2. 广东省科学院新材料研究所 广东省现代表面工程技术重点实验 室, 现代材料表面工程技术国家工程实验室, 广州 510650

    ×
  • ， 邓朝阳2

    机 构：

    2. 广东省科学院新材料研究所 广东省现代表面工程技术重点实验 室, 现代材料表面工程技术国家工程实验室, 广州 510650

    ×
  • ， 闫星辰2

    机 构：

    2. 广东省科学院新材料研究所 广东省现代表面工程技术重点实验 室, 现代材料表面工程技术国家工程实验室, 广州 510650

    ×
  • ， 马文有2

    机 构：

    2. 广东省科学院新材料研究所 广东省现代表面工程技术重点实验 室, 现代材料表面工程技术国家工程实验室, 广州 510650

    ×
  • ， 胡永俊1

    机 构：

    1. 广东工业大学 材料与能源学院, 广州 510006

    ×
  • ， 刘敏2

    机 构：

    2. 广东省科学院新材料研究所 广东省现代表面工程技术重点实验 室, 现代材料表面工程技术国家工程实验室, 广州 510650

    ×

1. 广东工业大学 材料与能源学院, 广州 510006；
2. 广东省科学院新材料研究所 广东省现代表面工程技术重点实验 室, 现代材料表面工程技术国家工程实验室, 广州 510650；

Effects of Master Alloy Powders on Electrochemical Performance of Selective Laser Melted TMZF Alloy

  • CHU Qingkun1,2

    Affiliation：

    1. College of materials and energy, Guangdong University of Technology, Guangzhou 510006 , China

    2. National Engineering Laboratory for Modern Materials Surface Engineering Technology, The Key Lab of Guangdong for Modern Surface Engineering Technology, Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510650 , China

    ×
  • ， DENG Zhaoyang2

    Affiliation：

    2. National Engineering Laboratory for Modern Materials Surface Engineering Technology, The Key Lab of Guangdong for Modern Surface Engineering Technology, Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510650 , China

    ×
  • ， YAN Xingchen2

    Affiliation：

    2. National Engineering Laboratory for Modern Materials Surface Engineering Technology, The Key Lab of Guangdong for Modern Surface Engineering Technology, Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510650 , China

    ×
  • ， MA Wenyou2

    Affiliation：

    2. National Engineering Laboratory for Modern Materials Surface Engineering Technology, The Key Lab of Guangdong for Modern Surface Engineering Technology, Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510650 , China

    ×
  • ， HU Yongjun1

    Affiliation：

    1. College of materials and energy, Guangdong University of Technology, Guangzhou 510006 , China

    ×
  • ， LIU Min2

    Affiliation：

    2. National Engineering Laboratory for Modern Materials Surface Engineering Technology, The Key Lab of Guangdong for Modern Surface Engineering Technology, Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510650 , China

    ×

1. College of materials and energy, Guangdong University of Technology, Guangzhou 510006 , China；
2. National Engineering Laboratory for Modern Materials Surface Engineering Technology, The Key Lab of Guangdong for Modern Surface Engineering Technology, Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510650 , China；

通讯作者:

刘敏(1965—),男(汉),教授级高级工程师,硕士;研究方向:激光增材制造、表面工程;E-mail:liumin@gdas.gd.cn

中图分类号:TG146.1;TG113.2

文献标识码:A

文章编号:1007-9289(2020)06-0128-08

DOI:10.11933/j.issn.1007-9289.20201021001

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目录contents

    摘要

    为了探究激光选区熔化( Selective laser melting, SLM) Ti-12Mo-6Zr-2Fe(TMZF) β 钛合金的腐蚀电化学行为,采用纯 Mo 粉末和 Mo-Fe 中间合金合金粉两种不同的 Mo 元素添加形式分别组成混合粉末进行激光增材制造,研究了中间合金粉末对 TMZF 合金试样组织与电化学性能的影响。 结合 X 射线衍射仪(XRD),金相显微镜(OM),扫描电子显微镜(SEM)、能谱分析(EDS)及腐蚀电化学等材料表征手段对 SLM TMZF 试样的物相分布、微观组织结构、元素分布及耐腐蚀性能进行了对比分析。 结果表明,单质混粉制备的 SLM-β-1 试样与中间合金混粉制备的 SLM-β-2 试样的组织中都含有大量的 β-Ti 组织,SLM-β-1 试样在 Bode 图中显示出更高的阻抗,Nyquist 图中 SLM-β-1 试样的容抗弧半径要大于 SLM-β-2 试样,动电位极化曲线中 SLM-β-1 试样的钝化膜击破电位要高于 SLM-β-2 试样。 综合对比发现单质混合粉末 SLM-β-1 试样的耐腐蚀性能要优于中间合金混合粉末 SLM-β-2 试样的耐腐蚀性能。

    Abstract

    In order to investigate the electrochemical corrosion behavior of selective laser melting (SLM) Ti-12Mo-6Zr-2Fe (TMZF) β titanium alloy, pure Mo powders and Mo-Fe master alloy powders were used to form mixed powders for laser additive manufacturing. The effect of master alloy powders on the microstructure and electrochemical properties of TMZF alloy sample was studied. The corrosion electrochemical properties of SLM TMZF samples fabricated via the two different mixed powders were systematically studied and compared. Phase composition, microstructural characteristics, elements distribution and corrosion resistance of the SLM TMZF samples were investigated using XRD, OM, SEM, EDS and electrochemical corrosion (EC). Results show that both SLM-β-1 (prepared by mixing a variety of pure metal powders) and SLM-β-2 (prepared by mixing intermetallic compounds powders) samples contain a large amount of β-Ti microstructure. SLM-β-1 sample show higher impedance in Bode plots. The capacitive arc radius of SLM-β-1 sample is larger than that of SLM-β-2 sample in Nyquist plots. The breakdown potential of passive film of SLM-β-1 sample in potentiodynamic polarization curve is higher than that of SLM-β- 2 sample. Comprehensive comparison show that the corrosion resistance of SLM-β-1 (prepared by mixing a variety of pure metal powders) sample is better than that of SLM-β-2 ( prepared by mixing intermetallic compounds powders) sample under different mixed powders.

  • 0 引言

  • 近年来,科学技术的进步促进了第四次工业革命的蓬勃发展,主要以增材制造、大数据和人工智能等先进技术为代表[1]。激光选区熔化技术(Selective laser melting, SLM)是新兴的一种金属增材制造技术。该技术是以三维数字模型文件为数据源[2-5],使用高能激光束对粉末床逐层进行选择性地熔化并凝固成形。高能激光源熔化得到的液体熔池迅速冷却, 冷却速度可达10 3~10 5 K/s [6],形成了一个个凝固熔道,之后, 相邻激光熔道快速熔化并凝固,随后的层层之间快速熔凝,最终得到近净成形零件。由于其可生产结构复杂零件的卓越能力,SLM技术已应用于各种制造领域,例如生物医学,航空航天和汽车工业,显示了其在未来制造市场的潜力[7-10]。

  • 由于人口老龄化的加剧,关节置换手术在全球范围内的需求量呈飞速增长态势。据报道,全世界每年大约有80万的患者需要进行初次关节置换手术,且年增长率近20%[11]。生物医用钛合金由于其优越的生物相容性、优良的机械性能以及接近人体皮质骨的低杨氏模量而具有广泛的医学应用[12-15]。同时,最近在生物医学钛合金方面的研究表明,新型 β 型钛合金[16-17]具有更好的生物相容性和较低的应力屏蔽效应,因此被认为能够比Ti-6Al-4V合金更有效地促进骨愈合和重塑[18-20]。近年来,有关SLM β 钛合金的研究持续进行。 LUO等[21] 采用SLM技术,通过调整工艺参数,制备出相对密度为96.8%~99.2%的Ti-30Nb-5Ta-3Zr(TNTZ)样品,研究了制备样品的弹性模量、疲劳性能和加工精度。研究表明,所制备的SLM TNTZ试样具有良好的生物相容性、较低的弹性模量和较高的力学性能。但其屈服强度较低为664MPa,低于铸态TNTZ的736MPa。 YANG等[22] 通过研究发现SLM制备的Ti-24Nb-4Zr-8Sn(Ti2448)的极限抗拉强度(UTS) 和均匀延伸率(UE) 与锻造相比同时提高。此外,还发现SLM制备样品的拉伸性能是各向异性的,与熔池形状的不规则性密切相关。但对于其耐腐蚀性能并未研究。 LUO等[23] 通过SLM技术制备了高强度塑性 β 型( Ti69.71Nb23.72Zr4.83Ta1.74) 97Si3( 原子数分数%)(TNZTS) 合金。所制备的TNZTS合金表现出978MPa的超高屈服强度,1010MPa的极限强度和10.4%的大延伸率,屈服强度比传统锻造的TNZT合金高出约55%。 ZHANG等[24] 使用SLM技术制备了生物医用 β 钛合金Ti-24Nb-4Zr-8Sn组件,包括髋臼杯样品。研究发现样品的相对密度随入射激光能量的增加而增加,并且在没有任何后处理的情况下达到接近99%的全密度值。但并未研究其在体液环境中的腐蚀行为。

  • 综上所述,目前对于SLM β 钛合金的研究主要集中在激光加工参数对于 β 钛合金微观结构和力学性能的影响,且所采用的粉末都是合金粉,而在采用混合粉末打印成形 β 钛合金以及对其腐蚀性能的影响方面研究较少。 Ti-12Mo-6Zr-2Fe( TMZF) 合金是一种亚稳态型 β 钛合金,其具有强度高、弹性模量低、耐蚀性能及耐磨损性能优良等特点,是一种理想的人造骨植入物生物材料,且已经得到临床医用方面的许可[25]。但是使用SLM技术制备低成本、高性能且耐腐蚀的TMZF合金并未得到较多研究,因此,文中研究拟使用球磨工艺自制TMZF合金粉末原材料, 使用SLM技术对合金成分相同但不同混粉成分配比的TMZF合金进行制备,并对其微观组织及耐腐蚀性能进行系统性研究,探讨不同混粉种类对SLM TMZF合金试样的微观结构、物相分布及耐腐蚀性能的影响。

  • 1 材料及方法

  • 1.1 试样制备

  • 所用纯Ti粉末(质量分数为99.9%)、纯Mo粉末(质量分数为99.9%)、质量分数为99.9%的纯Fe粉末(星尘科技有限公司,中国)均为球形粉末。为了防止Zr粉在球磨过程中发生爆炸, 研究中使用纯度为99.2%(质量分数)的ZrFe中间合金粉末代替纯Zr粉进行球磨混粉。另外, 由于Mo粉是一种熔点较高的难熔金属粉末,为了探讨纯Mo粉的加入对制备TMZF亚稳态型 β 钛合金的影响,使用纯Mo粉及MoFe不规则合金粉末(质量分数为98.3%) 分别进行混粉后再使用SLM技术进行制备。使用MAXN高精密度电子天平按照质量比Ti ∶Mo ∶Fe ∶ZrFe=40 ∶ 6 ∶3 ∶1的比例配置TMZF粉末,其中使用400g纯Ti粉,60g纯Mo粉,2.5g纯Fe粉和37.5g ZrFe粉,在研究中将采用这种比例所配粉末命名为 β-1。使用天平按照质量比Ti ∶ MoFe ∶ ZrFe=37 ∶ 10 ∶3的比例配置TMZF粉末,其中使用370g纯Ti粉,100g MoFe粉和30g ZrFe粉,将采用这种比例所配粉末命名为 β-2。将所配粉末使用QM-3SP4型行星球磨机进行球磨混粉,球磨工艺设置为转速150r/min,混粉时间1h。图1(a) 为 β-1混合粉末的粒度分布情况和粉末元素分布情况,图1(b)为 β-2混合粉末的分散分布情况和粉末元素分布情况。

  • 图1 β-1和 β-2混合粉末及原材料粉末的形貌、粒径分布及其制备的TMZF合金试样

  • Fig.1 Morphologies and particle size distribution of β-1and β-2mixed powders and raw material powders and TMZF alloy samples prepared

  • 为保证铺粉效果,减少粉末流动性对SLM零件成形性能的影响,所选上述粉末的粒径以10~50 μm为宜。图1( c) 为通过Mastersizer 3000型激光衍射粉末粒度仪测得的研究中所用粉末的粒度分布情况。粉末的具体粒径数值如表1所示。 SLM激光扫描策略如图2所示,即每层扫描后,下一层制备需旋转67°。使用EOS M290增材制造系统在Ti-6Al-4V基板上进行样品的制备。对激光参数进行系统优化后,研究的工艺参数设定如下:激光光斑为100 μm, 激光功率为230W,层厚为30 μm,扫描间距为110 μm,扫描速度为900mm/s,对SLM样品进行成形制备。样品制备时向成形仓通入高纯度氩气( 质量分数为99.99%),并将氧含量保持在1000ppm以下,以避免SLM样品制备过程中可能会出现的氧化现象。图1( d) 为使用SLM技术制备的用于组织观测和耐腐蚀测试的TMZF合金试样,将使用 β-1混合粉末制备的SLM试样命名为SLM-β-1,将使用 β-2混合粉末制备的SLM试样命名为SLM-β-2。

  • 表1 不同粉末的粒径分布值

  • Table1 Particle size distribution of different powders

  • 图2 在这项研究中使用的SLM扫描策略

  • Fig.2 SLM scanning strategy utilized in this study

  • 1.2 材料表征

  • 使用Leica DmirmMW550型光学显微镜和带有能谱仪系统的Nova nanoSEM430型扫描电子显微镜对SLM TMZF样品的微观结构进行表征。金相分析前,对所有样品用不同目数的SiC砂纸进行打磨并抛光,然后在含有100mL氢氟酸(HF)、300mL硝酸(HNO3)和600mL水(H2O) 的腐蚀液中腐蚀20s。使用RIGAKU公司产的Smartlab9kW型高分辨X射线衍射仪对SLM样品的物相组成进行分析,靶材为铜靶,扫描角度为30~80°,电压及电流为40kV和30mA。

  • 1.3 电化学性能

  • 使用商用电化学工作站(CorrTest-CS350H) 通过三电极法测试SLM-β-1和SLM-β-2试样的腐蚀电化学性能,进行包括动电位极化曲线(Potential dynamic polarization, PDP)和电化学阻抗谱( Electrochemical impedance spectroscopy, EIS)的测量。测试前,将SLM TMZF试样加工成10mm×10mm×6mm的试样后于其背面焊接一条金属导线,将其冷镶嵌在一个 ϕ30mm×20mm的环氧树脂柱中制成工作电极,对工作电极用不同目数的SiC砂纸进行打磨并抛光,然后将其紧密安装在有机玻璃圆筒状电解槽底部 ϕ=10mm的水平孔口上。对电极采用的铂片尺寸为15mm×15mm×0.1mm,平行地置于工作电极上方约10mm处。将KCl饱和甘汞电极( Saturated calomel electrode, SCE)作为参比电极,腐蚀电解液为模拟体液质量分数的3.5%NaCl溶液。在室温(约25℃)下使用频率从10mHz~100kHz, 固定振幅为10mV的正弦信号进行EIS的测量。然后在-1.0~1.5V的电位扫描范围内, 以1mV/s的扫描速率进行PDP的测量。

  • 2 结果与讨论

  • 2.1 物相组成

  • 对不同混合粉末打印的SLM TMZF合金试样进行XRD物相测试,结果如图3所示。由XRD衍射图谱可知,SLM-β-1与SLM-β-2试样的物相峰位基本相同,主要由 α′-Ti相、 β-Ti相组成,可能有少量的FeTi相和Fe0.54Mo0.73 相生成。其中 β-Ti相峰位最高,表明在激光选区熔化过程中,SLM TMZF合金试样中形成了较多的 β-Ti相。进一步验证了混合粉末SLM成形TMZF合金的可行性。

  • 图3 SLM-β-1与SLM-β-2试样的XRD图谱

  • Fig.3 XRD patterns of the SLM-β-1and SLM-β-2samples

  • 相对于标准 β-Ti相峰位( 2θ=38.481°), SLM-β-1试样,SLM-β-2的物相峰位均有偏移, 出现这样的结果,一方面是由于SLM制备过程中熔池凝固速度极快,冷却后的试样中存在着大量的热应力及组织应力,因此会导致组织晶格畸变,进而导致峰位发生偏移。另一方面则是由于打印所用的粉末是混合粉末,在激光熔融过程中合金化程度有限,可能有小半径杂质原子固溶于所形成的合金组织中从而导致晶格畸变,进而使得物相峰位偏移。

  • 此外,由于极高的能量输入导致铁粉与钼粉在制备过程中可能形成了高温不稳定相Fe0.54Mo0.73,但激光熔凝速度极快,熔池存在时间较短,因此制备过程中形成的不稳定相会存在于室温组织中。但由于形成的含量较少,在XRD图谱中只有1个峰位被检测到。此外,根据Fe-Ti相图可知,在1317~1530℃ 时,Fe与Ti较易发生冶金反应生成少量的FeTi化合物。因此, 在XRD图谱中可以检测到微量的FeTi化合物。总之,在采用混合粉末制备TMZF合金时,由于所用粉末不是完全的纯净粉末以及合金化程度有限,导致了组织中存在一定的中间合金相和一些峰位较低的杂质相。

  • 2.2 微观组织

  • 图4 为SLM-β-1试样的微观组织及主要元素分布情况。如图4( a)所示,SLM-β-1试样组织中除了有 β-Ti组织外,仍有较多细针状的 α′-Ti组织。由于激光熔凝冷速较快,针状 α′-Ti相呈细长柱状晶连续生长。如图4( b)所示,采用单质粉进行球磨的方式进行制备的SLM-β-1试样组织元素分布较为均匀,并未发现较为明显的偏析现象。证明使用单质粉末混粉后进行SLM制备是一种成本低廉、方式简单且易获得SLM TMZF亚稳态型 β 钛合金的可行方法。但由于Mo粉熔点(2623℃) 较高,且与Ti粉( 1668℃)、 Fe粉( 1538℃) 和ZrFe粉( 约1600℃)熔点相差较大,因此使用单质粉混粉后仍有较多难熔球形Mo粉分布在合金组织中, 如图4( c)、4( d) 所示。因此,引入中间合金采用相同成分进行配比后制粉的方式则成为一种可能成功的较好思路。

  • 图4 SLM-β-1试样的微观组织

  • Fig.4 Microstructure of SLM-β-1sample

  • 为了解决上述问题,得到更多更稳定的 β-Ti相。采用引入中间合金代替单质钼粉的方式,使用SLM技术成功制备了SLM TMZF合金, 即SLM-β-2试样。其微观组织如图5所示。如图5(a)所示为SLM-β-2试样的金相组织,可以清晰地看到有大量的 β-Ti组织。如图5( b) 所示,在放大倍数的SEM中可以看到颗粒状的 α′-Ti组织从 β-Ti网篮组织边界处析出。与SLM-β-1试样组织相比,形成的网篮组织较为粗大。通过EDS分析,即图5( c)中的主要元素分布可以看出,单质混粉后进行SLM制备导致的未熔球状Mo粉粒子并不存在,但晶内与晶间元素分布出现了偏析现象,出现这种现象的原因可能是由于粉床中的MoFe粉和ZrFe粉是中间合金,在SLM熔化过程中尽管有进一步的冶金反应发生, 但是由于凝固速度过快,导致MoFe和ZrFe来不及熔融并形成新的无偏析 β-Ti组织,因此元素出现了较为明显的偏析现象。

  • 图5 SLM-β-2试样的微观组织

  • Fig.5 Microstructure of SLM-β-2samples

  • 2.3 不同成分混合粉末对Ti12Mo6Zr2Fe合金电化学性能的影响

  • Randles模型(R(QR))通常用于表征表面电化学状态。图6为Randles模型的等效电路,其中 Rs 是溶液电阻,CPE 是常相位角元件,此处用于表征钝化层的恒定相位元件,Rp 是钝化层的极化电阻。 CPE 被广泛用于表征具有电容和电阻特性的涂层或薄膜(例如,在这项研究工作中在样品表面上形成的钝化层)的电化学行为。

  • 图6 EIS等效电路示意图

  • Fig.6 Equivalent circuit diagram of EIS

  • SLM-β-1和SLM-β-2试样的Bode图如图7(a)所示。在10 3~10 5 Hz的范围内,相角下降至接近0°, | Z |逼近于 Rs,这表明 Rs 主导了腐蚀行为。在10 3 Hz~1Hz的范围内,相位图一直增加直到达到最大相位角,然后转向一个平台阶段,但是两条| Z | 曲线却呈线性增加,这种现象通常表明 CPE 占主导地位。在1Hz~10-2 Hz的低频范围内,两条 | Z | 曲线不断增加,其中SLM-β-1试样显示出更高的阻抗,表明其耐腐蚀性相对较好。表2列出了相应的阻抗谱拟合参数,其中 Rs 是溶液电阻,CPE 是常相位角元件,Rs 是钝化层的极化电阻,np 为 CPE 系数,R(QR) 为Randles模型。对于SLM-β-1和SLM-β-2试样,所有参数的相对误差均小于10%。这意味着Randles模型适用于SLM-β-1和SLM-β-2试样。

  • 图7 SLM TMZF合金试样在3.50%NaCl溶液中的Bode图和Nyquist图

  • Fig.7 Bode plots and Nyquist plots of the SLM TMZF alloy samples in 3.50%NaCl solution

  • 表2 3.50%NaCl溶液中SLM TMZF合金试样电化学阻抗谱拟合参数

  • Table2 Fitting parameters of the EIS measurements of the SLM TMZF alloy samples in 3.50%NaCl solution

  • 图7( b) 为SLM-β-1和SLM-β-2试样在3.50%NaCl溶液中的Nyquist图。如图7所示, SLM-β-1和SLM-β-2试样的阻抗谱图都表现出容抗弧特征,试样表面的氧化膜为单层结构。在单一容抗弧的交流阻抗谱图中,容抗弧的半径越大,说明合金表面转移电阻就越大,则表明其耐腐蚀性越好。由图7(b)可以看出,SLM-β-1试样的半径明显要大于SLM-β-2合金试样,说明在3.50%NaCl溶液中SLM-β-1试样的耐腐蚀性要优于SLM-β-2试样,出现这种情况的原因可能是由于SLM-β-2试样中的网篮组织较为粗大,元素在枝晶组织中和晶间组织的元素偏析较为明显, 因此导致其耐腐蚀性略微下降。

  • 对SLM-β-1和SLM-β-2试样以1mV/s的扫描速率在-1~1.50V的范围内进行电位扫描, 获得了动电位极化曲线(PDP),如图8所示。腐蚀参数如表3所示,其中 Icorr 为腐蚀电流密度, Ecorr 为腐蚀电位。在-0.75V到-0.25V之间观察到典型的极化行为,SLM-β-1试样在-0.51V时的极化电流密度最低约为5.59×10-3 μA·cm-2, SLM-β-2试样在-0.45V时的极化电流密度最低约为9.54 × 10-4 μA·cm-2。当电位增加到1.5V时,SLM-β-1试样极化电流密度增加到87.8 μA·cm-2,SLM-β-2试样极化电流密度增加到49.70 μA·cm-2。通过进行极化,钝化层被击破,从而使样品被腐蚀,随着腐蚀反应明显加剧,极化曲线出现电流峰。此后,电流密度再次下降,这主要是由于产生了新的钝化层。如表3所示,虽然SLM-β-2试样的 Icorr 要小于SLM-β-1试样的 Icorr,但由于TMZF试样表面存在钝化膜, 且根据极化曲线可知,SLM-β-1试样的击破电位要略高于SLM-β-2试样的击破电位。因此, SLM-β-1试样的耐腐蚀性相对较好。

  • 图8 SLM TMZF合金试样在3.50%NaCl溶液中的动电位极化曲线

  • Fig.8 Potentialdynamic polarization curve of SLM TMZF alloy samples in 3.50%NaCl solution

  • 表3 PDP中的腐蚀参数

  • Table3 Corrosion parameters obtained from the PDP measurements

  • 3 结论

  • 文中研究了不同混合粉末对SLM TMZF成形性、微观组织以及耐腐蚀性的影响,获得了较好耐蚀性的TMZF合金,得到以下具体结论:

  • (1) 通过混粉以及SLM成功地制备了SLM TMZF合金试样。虽然采用了不同的混合粉末, 但SLM-β-1和SLM-β-2试样的物相组成基本相同,主要由 α′-Ti相和 β-Ti相组成,还有少量的FeTi相和Fe0.54Mo0.73 相。

  • (2) SLM-β-1试样组织中除了有 β-Ti组织外,仍有较多细针状的 α′-Ti组织,针状 α′-Ti相呈细长柱状晶连续生长,且组织中含有未熔的Mo粉颗粒;SLM-β-2试样组织中含有大量的β-Ti组织以及颗粒状的 α′-Ti组织,但晶内与晶间元素分布出现了偏析现象。

  • (3) 电化学性能中,SLM-β-1试样在Bode图中显示出更高的阻抗,Nyquist图中SLM-β-1试样的容抗弧半径要大于SLM-β-2试样的容抗弧半径,动电位极化曲线中SLM-β-1试样的钝化膜击破电位要高于SLM-β-2试样钝化膜击破电位。

  • 参考文献

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  • 基本信息

    中图分类号: TG146.1;TG113.2
    文献标识码: A
    DOI: 10.11933/j.issn.1007-9289.20201021001
    文章编号: 1007-9289(2020)06-0128-08

    基金信息

    广东省科学院专项资金项目(2021GDASYL-20210102005)；
    Supported by Special Fund Project of GDAS (2021GDASYL-20210102005)；

    引用信息

    褚清坤, 邓朝阳, 闫星辰, 等. 中间合金粉对激光选区熔化 TMZF 合金电化学性能的影响[J]. 中国表面工程, 2020, 33(6): 128-135.

    CHU Q K, DENG Z Y, YAN X C, et al. Effects of master alloy powders on electrochemical performance of selective laser melted TMZF alloy[J]. China Surface Engineering, 2020, 33(6): 128-135.

    稿件历史

    收稿日期: 2020-10-21

  • 参考文献

    • [1] CHANG C,YAN X C,BOLOT R,et al.Influence of postheat treatments on the mechanical properties of CX stainless steel fabricated by selective laser melting [J].Journal of Materials Science,2020,55(19):8303-8316.

    • [2] YAN X C,CHEN C Y,CHANG C,et al.Study of the microstructure and mechanical performance of C-X stainless steel processed by selective laser melting(SLM)[J].Materials Science and Engineering:A,2020,781:139227.

    • [3] YAN X C,YIN S,CHEN C Y,et al.Fatigue strength improvement of selective laser melted Ti6Al4V using ultrasonic surface mechanical attrition [J].Materials Research Letters,2019,7(8):327-333.

    • [4] YAN X C,HUANG C J,CHEN C Y,et al.Additive manufacturing of WC reinforced maraging steel 300 composites by cold spraying and selective laser melting [J].Surface and Coatings Technology,2019,371:161-171.

    • [5] DONG D D,CHANG C,WANG H,et al.Selective laser melting(SLM)of CX stainless steel:Theoretical calculation,process optimization and strengthening mechanism [J].Journal of Materials Science & Technology,2021,73:151-164.

    • [6] AL-RUBAIE K S.,MELOTTI S,RABELO A,et al.Machinability of SLM-produced Ti6Al4V titanium alloy parts [J].Journal of Manufacturing Processes,2020,57:768-786.

    • [7] VANDENBROUCKE B,KRUTH J P.Selective laser melting of biocompatible metals for rapid manufacturing of medical parts [J].Rapid Prototyping Journal,2007,13(4):196-203.

    • [8] THIJS L,VERHAEGHE F,CRAEGHS T,et al.A study of the microstructural evolution during selective laser melting of Ti-6Al-4V [J].Acta Materialia,2010,58(9):3303-3312.

    • [9] YAN X C,YIN S,CHEN C Y,et al.Effect of heat treatment on the phase transformation and mechanical properties of Ti6Al4V fabricated by selective laser melting [J].Journal of Alloys and Compounds,2018,764:1056-1071.

    • [10] YAN X C,LI Q,YIN S,et al.Mechanical and in vitro study of an isotropic Ti6Al4V lattice structure fabricated using selective laser melting [J].Journal of Alloys and Compounds,2019,782:209-223.

    • [11] BELATTI D A,PUGELY A J,PHISITKUI A J,et al.Total joint arthroplasty:Trends in medicare reimbursement and implant prices [J].The Journal of Arthroplasty,2014,29(8):1539-1544.

    • [12] LIU X Y,CHU P K,DING C X.Surface modification of titanium,titanium alloys,and related materials for biomedical applications [J].Materials Science and Engineering:R:Reports,2004,47(3):49-121.

    • [13] YOSHIDA Y,MINE A,FUJISAWA T,et al.Chemical interaction of polyphosphoric acid with titanium and its effect on human bone marrow derived mesenchymal stem cell behavior [J].Journal of Biomedical Materials Research Part A,2007,82:195-200.

    • [14] HU L,GUO S,MENG Q K,et al.Metastable β-type Ti30Nb-1Mo-4Sn alloy with ultralow young’ s modulus and high strength [J].Metallurgical and Materials Transactions A,2014,45(2):547-550.

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