CuZr等原子比合金课件

1、Al、Ti、Ni添加制备CuZr等原子比合金及结构和性能报告人：*- 导师：汇报内容研究背景及意义1高熵合金的特性与制备方法2我的工作4文献调研31研究背景及意义高熵合金的定义定义：具有5种或者5种以上合金元素以等摩尔比或近等摩尔比 混合形成的固溶体合金。判断：3(两种元素以等摩尔混合)当 n=2 时，S= 0.693R，当 n=5 时，S= 1.61R当 n=6 时，S= 1.79R当 n= 9时，S= 2.20R 高熵的定义标准原子半径差控制在15%左右；每一种主元的含量需要5%，小于35 %；主元数目应大于5，最好不超过131研究背景及意义高熵合金的分类按熵值对高熵合金进行分类可以分为：

2、低熵合金、中熵合金、和高熵合金。分类的示意图如下图所示：40.69RS1.61R2高熵合金的特性与制备方法高熵效应和迟滞扩散效应高熵效应：高熵合金中元素种类较多，因此合金系统具有较高的熵值，而金属间化合物的相是有序的，从而其混合熵较低，因此金属间化合物的形成得到抑制而倾向于产生结构简单的晶体或者非晶相，从而产生了高熵效应。迟滞扩散效应：应近几年，Yeh等人研宄发现HEAs与不锈钢和纯金属相比，其元素的扩散速率最低，这导致HEAs产生迟滞扩散效应。这种效应导致晶体形核容易但是长大难，因此通常用于解释HEAs中纳米尺寸析出物的产生。52高熵合金的特性与制备方法晶格畸变效应和鸡尾酒效应晶格畸变效应：

3、HEAs是多组元等原子比组成，因此组成元素占据晶格位置的比例是相等的，但是每种元素的原子半径差值较大，将会导致严重的晶格畸变，这将导致合金的晶格畸变能增加，从而导致固溶强化作用加强。这往往导致HEAs具有较强的强度与硬度等优异的性能。鸡尾酒效应：鸡尾酒效应表明了通过改变合金的组成成分可以改变合金相应的性能。在HEAs中，添加一种特定的元素可以获得某种特定的优异的性能，然而这种性能是由单一元素不能获得的。62高熵合金的特性与制备方法铸造法铸造法：制备高熵合金最常用的铸造法是真空熔炼法。7等离子熔覆法粉末冶金法等离子熔覆法：利用高能的电子束将基体上的高熵合金熔化，形成熔覆层。粉末冶金：利用压制或者

4、烧结把机械合金化的粉末制备成试样。制备方法：3文献调研文献一机械合金化法和放电等离子烧结制备块体CuZrAl和CuZrAlTi中熵合金结构和性能8文献二机械合金化法和放电等离子烧结制备块体CuZr等原子比合金和CuZrAlTiNi高熵合金结构和性能文献的研究目的和意义选择CuZr为原型、设计含CuZr等原子比合金为研究对象，添加非晶合金常用的Al、Ti、Ni元素，利用MA等原子比合金粉末，研究了不同组元等原子比合金粉末的微观结构和热学性能。探索SPS烧结工艺，利用SPS烧结大块等原子比合金。同时对块体合金的相组成，微观组织，硬度及耐腐蚀性进行较为系统的研究。文献研究的方案基本研究路线耐蚀性SE

5、M极化曲线机械合金化SPS烧结硬度XRD（物相分析）DSC（差热分析）SEM（形貌观察）XRD（物相分析）SEM（形貌观察）合金粉末大块合金机械合金化CuZrAl和CuZrAlTi等原子比合金粉末XRD分析11Fig. 1. XRD patterns of as-milled E3 ( a) and ( b) powders after different MA time. 球磨10 h,Al和Ti元素均完全固溶，出现富Zr-hcp和富Ti-hcp类型的固溶体附峰；球磨20h后，只有非晶相及富Zr-hcp固溶体存在。球磨30h后出现完全的非晶相。Wenjuan Ge Xuting Li, Pe

6、ngchao Qiao, Jianwei Du, Shuai Xu, Yan Wang. Microstructure and properties of CuZrAl and CuZrAlTi medium entropy alloys prepared by mechanical alloying and spark plasma sinteringJ. Journal of Iron and Steel Research, International, 2017, 24: 448-457. 球磨10 h,有富Zr-hcp类的固溶体相。球磨到120 h，一个完全的非晶相产生，且到200h非

7、晶相依然稳定的存在。机械合金化CuZrAl和CuZrAlTi等原子比合金粉末DSC和形貌分析12Fig. 2. DSC traces of as-milled E3 and E4 alloys at 20 K/ min heating rate (a, b), and FESEM images and EDS spectrum ( inset) of as-milled E3 (c) and E4, (d) powders after 200 h milling.Table 1 Thermal parameters of as-milled E3 and E4 powders after 20

8、0 h milling. 两种合金粉末均出现了放热峰，表明合金发生晶化行为，这也证明了非晶相的存在。球磨的粉末呈现出颗粒状，并且具有均匀分布的尺寸Wenjuan Ge Xuting Li, Pengchao Qiao, Jianwei Du, Shuai Xu, Yan Wang. Microstructure and properties of CuZrAl and CuZrAlTi medium entropy alloys prepared by mechanical alloying and spark plasma sinteringJ. Journal of Iron and St

9、eel Research, International, 2017, 24: 448-457. CuZrAl和CuZrAlTi等原子比块状合金的XRD分析13Fig. 3. XRD patterns of as-sintered E3 (a) and E4 (b) alloys at different sintering temperatures. E3合金是由FCC固溶体Al1.05Cu0.95Zr和AlZr2两种金属间化合物组成。E4合金在低温烧结完全是由金属间化合物组成，高温烧结时产物主要有FCC1+FCC2固溶体加上CuTi3金属间化合物组成。Wenjuan Ge Xuting Li

10、, Pengchao Qiao, Jianwei Du, Shuai Xu, Yan Wang. Microstructure and properties of CuZrAl and CuZrAlTi medium entropy alloys prepared by mechanical alloying and spark plasma sinteringJ. Journal of Iron and Steel Research, International, 2017, 24: 448-457. CuZrAl等原子比块状合金的形貌14Fig. 4. FESEM images and m

11、agnified figures (inset) of as-sintered E3 bulk alloy sintered at 700 (a, b), and 1050 (e, f) ; and EDS spectra of different regions (c, d) and (g, h) corresponding to (b) and (f) , respectively. 亮区富含Cu、暗区富含Al、Zr。说明Cu易偏析到边界。高温合金中，有许多纳米析出物均匀分布在。Wenjuan Ge Xuting Li, Pengchao Qiao, Jianwei Du, Shuai X

12、u, Yan Wang. Microstructure and properties of CuZrAl and CuZrAlTi medium entropy alloys prepared by mechanical alloying and spark plasma sinteringJ. Journal of Iron and Steel Research, International, 2017, 24: 448-457. CuZrAlTi等原子比块状合金的形貌15Fig. 5. FESEM images and magnified figures (inset) of as-sin

13、tered E2 alloy sintered at 690(a, b), and 1100 (e, f); and EDS spectra of different regions (c, d) and (g, h) corresponding to (b) and (f) , respectively. Al元素富含于边界处。Ti元素的添加阻碍了Cu元素的偏析，且促进了均匀结构的产生。Wenjuan Ge Xuting Li, Pengchao Qiao, Jianwei Du, Shuai Xu, Yan Wang. Microstructure and properties of Cu

14、ZrAl and CuZrAlTi medium entropy alloys prepared by mechanical alloying and spark plasma sinteringJ. Journal of Iron and Steel Research, International, 2017, 24: 448-457. CuZrAl和CuZrAlTi块状合金硬度分析16Fig. 6. Hardness of as-sintered E3 and E4, alloys at different stntermg temperatures. E4合金与E3合金相比，硬度值偏高分

15、析原因可能是以下几点：E4合金迟滞扩散效应加强，纳米析出物增多且弥散分布。E4-1100合金主要是由固溶体构成，固溶体作为增强相。E4-1100合金的烧结密度较高，达到99.6%Wenjuan Ge Xuting Li, Pengchao Qiao, Jianwei Du, Shuai Xu, Yan Wang. Microstructure and properties of CuZrAl and CuZrAlTi medium entropy alloys prepared by mechanical alloying and spark plasma sinteringJ. Journa

16、l of Iron and Steel Research, International, 2017, 24: 448-457. CuZrAl和CuZrAlTi块状合金电化学腐蚀分析17Fig. 7. Potentiodynamic polarization curves of as-sintered E3, and E4alloys at different sintering temperatures. 样品以及304不锈钢均出现了钝化膜；E4低温合金的耐点腐蚀性能好；高温下合金的耐点腐蚀性能就比较差。E4合金出现两次钝化现象。Table 4 Corrosion parameters of

17、the tested samples in the seawater solutionWenjuan Ge Xuting Li, Pengchao Qiao, Jianwei Du, Shuai Xu, Yan Wang. Microstructure and properties of CuZrAl and CuZrAlTi medium entropy alloys prepared by mechanical alloying and spark plasma sinteringJ. Journal of Iron and Steel Research, International, 2

18、017, 24: 448-457. 结论18通过机械合金化和放电等离子烧结制备了CuZrAl和CuZrAlTi块状中熵合金，并详细研究了合金的合金化行为、相变、微观结构和性能。合金主要是由非晶相组成，Ti的添加提高了非晶形成能力。CuZrAl块状合金主要是由fcc固溶体、Al1.05Cu0.95Zr和AlZr2金属间化合物组成。CuZrAlTi块状中熵合金在低温下只由金属间化合物组成，高温下合金由fccl, fcc2 和 CuTi3相组成 。高温合金由于高密度，固溶强化和纳米尺寸结晶相的均匀沉淀硬度值达到了1173HV0.2。CuZrAlTi中熵合金表现出与304L不锈钢类似的耐腐蚀性，腐蚀速

19、率较低，耐蚀性较好。 所有烧结块体合金的腐蚀速率均低于304L。Wenjuan Ge Xuting Li, Pengchao Qiao, Jianwei Du, Shuai Xu, Yan Wang. Microstructure and properties of CuZrAl and CuZrAlTi medium entropy alloys prepared by mechanical alloying and spark plasma sinteringJ. Journal of Iron and Steel Research, International, 2017, 24: 44

20、8-457. 机械合金化CuZr和CuZrAlTiNi等原子比合金粉末XRD分析19Figure 1 XRD patterns of the as-milled E2 (a) and E5 (b) powders after different MA times.球磨5h后，球磨产物仍包含初始元素粉末的混合物，但是衍射峰明显变宽，且强度很低；球磨10h后，球磨产物有富Zr-hcp结构和富Cu-fcc结构；球磨200h后，非晶相仍然存在。球磨5h后，球磨产物与初始元素粉末的混合物相似，但是衍射峰明显变宽（是由于晶粒尺寸减少）；球磨10h后，Al元素的衍射峰消失，并且有富Zr-hcp结构、富Cu-

21、fcc结构、富Ti-hcp和富Ni-fcc类型的固溶体相，球磨到20h,球磨粉末为完全的非晶相；球磨200h后，非晶相仍然存在。WenjuanGe Yingzi Wang, Caiyun Shang, Zitang Zhang, Yan Wang. Microstructures and properties of equiatomic CuZr and CuZrAlTiNi bulk alloys fabricated by mechanical alloying and spark plasma sinteringJ. Journal of Materials Science, 2017,

22、 52: 5726-5737. 机械合金化CuZr和CuZrAlTiNi等原子比合金粉末DSC和形貌分析20Figure 2 DSC traces of the as-milled E2 and E5 alloys at the heating rate of 20 K/min (a), and FESEM images of the as-milled E2 (b) and E5 (c) powders after 200 h milling time.E2合金的初始晶化温度比E5合金的低，说明E2合金具有更好的烧结条件。出现放热峰，说明合金粉末发生了晶化行为，并进一步证明了非晶相的存在。从

23、合金粉末的微观形貌可以观察出E5合金的颗粒更加的细小。WenjuanGe Yingzi Wang, Caiyun Shang, Zitang Zhang, Yan Wang. Microstructures and properties of equiatomic CuZr and CuZrAlTiNi bulk alloys fabricated by mechanical alloying and spark plasma sinteringJ. Journal of Materials Science, 2017, 52: 5726-5737. CuZr和CuZrAlTiNi等原子比块状

24、合金XRD分析21Figure 3 XRD patterns of the as-sintered E2 (a) and E5 (b) bulk alloys at different sintering temperatures. The insets in (a) and (b) show the photographs of the as-sintered E2 and E5 bulk samples, respectively.E2-520是由非晶相、fcc固溶体、Cu8Zr3和富Zr的bcc类固溶体。E2-850是由fcc固溶体富Zr的bcc类固溶体、Cu8Zr3、Cu10Zr7和一

25、些未知相。E5-620是由bcc、fcc1+fcc2固溶体和AlNi2Zr金属间化合物组成。E5-950也是由由bcc、fcc1+fcc2固溶体和AlNi2Zr金属间化合物组成。WenjuanGe Yingzi Wang, Caiyun Shang, Zitang Zhang, Yan Wang. Microstructures and properties of equiatomic CuZr and CuZrAlTiNi bulk alloys fabricated by mechanical alloying and spark plasma sinteringJ. Journal of

26、 Materials Science, 2017, 52: 5726-5737. AlNi2Zr金属间化合物形成的原因22对于Zr、Ni、Al三种元素，其两两之间的不同原子配对的混合焓是在-22到-49KJ/mol范围内，说明三种元素之间具有很强的化学吸附性去吸附彼此。Zr、Al、Ni的电负性分别是1.33,1.61和1.92三者的差值较大，也容易形成金属间化合物。AlNi2Zr的电子浓度计算值为1.75，这正是典型的具有hcp结构的金属间化合物的电子浓度值。WenjuanGe Yingzi Wang, Caiyun Shang, Zitang Zhang, Yan Wang. Microst

27、ructures and properties of equiatomic CuZr and CuZrAlTiNi bulk alloys fabricated by mechanical alloying and spark plasma sinteringJ. Journal of Materials Science, 2017, 52: 5726-5737. CuZr等原子比块状合金形貌分析23Figure 4 FESEM micrographs of the as-sintered E2 bulk samples sintered at 520 C (a), and 850 C (b,

28、 c), and elemental mappings (d, e) corresponding to (c).E2低温合金中仍然存在一些空隙(箭头所示)但在相邻的颗粒之间形成了烧结颈，（圈出区域）E2高温合金没有任何的空隙存在，说明烧结质量很好。Zr和Cu元素分别主要分布在基体相和相边界处WenjuanGe Yingzi Wang, Caiyun Shang, Zitang Zhang, Yan Wang. Microstructures and properties of equiatomic CuZr and CuZrAlTiNi bulk alloys fabricated by me

29、chanical alloying and spark plasma sinteringJ. Journal of Materials Science, 2017, 52: 5726-5737. CuZr等原子比块状合金形貌分析24Figure 4 FESEM micrographs of the as-sintered E2 bulk samples sintered at 850 C (b)点1处（相边界）富含Cu元素，而点2处富含Zr元素（基体相）根据XRD分析结果可以得出，相的边界主要是Cu10Zr7而基体相主要是富cr-bcc固溶体相。Table 3 Chemical composi

30、tions of the as-sintered E2 bulk alloy sintered at 850WenjuanGe Yingzi Wang, Caiyun Shang, Zitang Zhang, Yan Wang. Microstructures and properties of equiatomic CuZr and CuZrAlTiNi bulk alloys fabricated by mechanical alloying and spark plasma sinteringJ. Journal of Materials Science, 2017, 52: 5726-

31、5737. CuZrAlTiNi等原子比块状合金形貌分析25Figure 5 FESEM micrographs of the as-sintered E5 bulk samples sintered at 620 C (a), and 950 C (b)E5低温合金中也产生了一些空隙但在相邻的颗粒之间形成了烧结颈（图中圈出来的部分），说明了试样的密度增加且发生了收缩。E5高温合金没有任何的空隙和其它杂质，说明烧结质量很好。WenjuanGe Yingzi Wang, Caiyun Shang, Zitang Zhang, Yan Wang. Microstructures and prope

32、rties of equiatomic CuZr and CuZrAlTiNi bulk alloys fabricated by mechanical alloying and spark plasma sinteringJ. Journal of Materials Science, 2017, 52: 5726-5737. CuZrAlTiNi等原子比块状合金形貌分析26Figure 5 FESEM micrographs of the as-sintered E5 bulk samples sintered at 950 C ( c), and elemental mappings (

33、dh) corresponding to (c).WenjuanGe Yingzi Wang, Caiyun Shang, Zitang Zhang, Yan Wang. Microstructures and properties of equiatomic CuZr and CuZrAlTiNi bulk alloys fabricated by mechanical alloying and spark plasma sinteringJ. Journal of Materials Science, 2017, 52: 5726-5737. CuZr和CuZrAlTiNi等原子比块状合金

34、硬度分析27Figure 6 Hardness of the as-sintered E2 and E5 bulk alloys at different sintering temperatures.均匀分布的细小的析出物将会导致高的硬度值AlNi2Zr金属间化合物作为第二相起到了增强的作用。具有最大原子半径的Zr元素占据晶格位置时，将会加剧晶格畸变程度。从而使得晶格畸变能增加，最终固溶强化效应加强。WenjuanGe Yingzi Wang, Caiyun Shang, Zitang Zhang, Yan Wang. Microstructures and properties of eq

35、uiatomic CuZr and CuZrAlTiNi bulk alloys fabricated by mechanical alloying and spark plasma sinteringJ. Journal of Materials Science, 2017, 52: 5726-5737. CuZr和CuZrAlTiNi等原子比块状合金耐腐蚀性分析28E5-650合金具有最正的腐蚀电位（-0.8790.02V），较低的腐蚀电流密度（3.470.39）10-5和较宽的钝化区（0.945V）表明其整体耐腐蚀性较好。E5-950合金具有较宽的钝化区（1.168V）表明耐点腐蚀性能优

36、异。Table 4 Corrosion parameters of the tested samples in the seawater solutionFigure 7 Potentiodynamic polarization curves of the as-sintered E2 and E5 bulk alloys at different sintering temperatures WenjuanGe Yingzi Wang, Caiyun Shang, Zitang Zhang, Yan Wang. Microstructures and properties of equiatomic CuZr and CuZrAlTiNi bulk alloys fabricated by mechanical alloying and spark plasma sint