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金屬頂刊雙語導讀丨Scripta Mater. Vol.202, 1 Sep. 2021（上）

2021-07-04 來源：GS_Metals

 

本期包含金屬材料領域論文8篇，涵蓋了高熵合金、增材制造、高溫合金等，國內科研單位包括北京科技大學等（通訊作者單位）。

 

Vol. 202 目錄

1. Design of a new cobalt base nano-lamellar eutectic high entropy alloy

一種新型鈷基納米層狀共晶高熵合金的設計

 

2. Hierarchical structure in Al-Cu alloys to promote strength/ductility synergy

Al-Cu合金中的層次結構促進強度/塑性的協同作用

 

3. Role of deformation twinning in fatigue of CrCoNi medium-entropy alloy at room temperature

變形孿晶在CrCoNi中熵合金室溫疲勞中的作用

 

4. High strength NiMnFeCrAlCu multi-principal-element alloys with marine application perspective

高強度NiMnFeCrAlCu多主元素合金在海洋中的應用前景

 

5. Vacancy surface migration mechanisms in dilute nickel-chromium alloys

稀Ni-Cr合金中的空位表面遷移機制

 

6. Effect of alloying elements on the coarsening rate of γ? precipitates in multi-component CoNi-based superalloys with high Cr content

合金元素對高Cr多組分CoNi基高溫合金γ?析出相粗化速率的影響

 

7. Dual plateau stress of C15-type topologically close-packed lattice structures additive-manufactured by laser powder bed fusion

通過激光粉末床熔合技術增材制造的C15型拓撲密排晶格結構的雙平臺應力

 

8. Simultaneous deformation twinning and martensitic transformation in CoCrFeMnNi high entropy alloy at high temperatures

CoCrFeMnNi高熵合金在高溫下同時產生變形孿晶和馬氏體相變

 

 

SCRIPTA

Vol. 202, 1 Sep. 2021, 113993

1. Design of a new cobalt base nano-lamellar eutectic high entropy alloy

一種新型鈷基納米層狀共晶高熵合金的設計

 

R. J. Vikram, Kushagra Gupta, Satyam Suwas?

Satyam Suwas: satyamsuwas@iisc.ac.in 

https://doi.org/10.1016/j.scriptamat.2021.113993

 

摘要

受鈷基高溫合金優異性能的啟發，以價電子濃度(VEC)為基礎開發了鈷基高溫高熵合金(HEA)。新開發的鈷基高熵合金具有納米層狀共晶形貌的兩相組織。通過相圖計算(CALPHAD)驗證了組成相為面心立方(FCC)和有序立方(B2)結構。新開發的HEA在室溫下表現出顯著的應變硬化行為，并在500-800℃的溫度范圍內表現出熱穩定性。

向上滑動閱覽英文摘要

Inspired by the outstanding properties of cobalt-base superalloys, an effort has been made to develop cobalt-base high entropy alloy for high temperature applications based on valance electron concentration (VEC). The newly developed cobalt-base high entropy alloy exhibited a two-phase microstructure with nano lamellar eutectic morphology. The constituent phases were identified as face centered cubic (FCC) and ordered cubic (B2) structure, which were validated through CAlculation of PHAse Diagram (CALPHAD). The newly developed HEA exhibited remarkable strain hardening behavior at room temperature as well as thermal stability in the temperature range 500-800 °C.

 

 

SCRIPTA

Vol. 202, 1 Sep. 2021, 113996

2. Hierarchical structure in Al-Cu alloys to promote strength/ductility synergy

Al-Cu合金中的層次結構促進強度/塑性的協同作用

 

S. H. Wu, H. Xue, C. Yang, J. Kuang, P. Zhang, J.Y. Zhang, Y.J. Li, Hans J. Roven?, G. Liu?, J. Sun?

Hans J. Roven: hans.j.roven@ntnu.no 

G. Liu: lgsammer@mail.xjtu.edu.cn  西安交通大學

J.Sun: junsun@mail.xjtu.edu.cn  西安交通大學

https://doi.org/10.1016/j.scriptamat.2021.113996

 

摘要

實驗結果表明，與室溫下的等通道轉角擠壓(ECAP)相比，低溫下的ECAP能促進Al-2.5wt.%Cu的強度-塑性協同作用。兩者的同時改善與多峰晶粒的組織層次、低角度晶界和晶間/晶內的析出相有關，這可以通過時效處理配合低溫ECAP來調節。人工時效可以保持多峰晶粒尺寸分布，引入大量低角度晶界，產生晶內析出相，從而提高合金的強度/塑性。0.3 wt.% Sc的添加可有效優化合金的析出，進一步提高合金的強度/塑性組合。低溫ECAP對強度和塑性提高的潛在機制是合理的。

向上滑動閱覽英文摘要

 

Experimental evidence demonstrated that equal channel angular pressing (ECAP) at cryogenic temperature, in comparison with ECAP at room temperature, led to promoted strength-ductility synergy in an Al-2.5wt.%Cu alloy. The simultaneous improvement is related to microstructural hierarchy of multimodal grains, low angle grain boundaries, and inter/intragranular precipitates, which was tuned by aging treatment in match with the low-temperature ECAP. The artificial aging could maintain multimodal grain size distribution, introduce a large number of low angle grain boundaries and produce intragranular precipitates to improve strength/ductility. A minor 0.3wt.% Sc addition was effective in optimizing the precipitations and further boosting the strength/ductility combination. The underlying mechanisms for higher strength and greater ductility were rationalized in terms of the low-temperature ECAP.

 

 

SCRIPTA

Vol. 202, 1 Sep. 2021, 113985

3. Role of deformation twinning in fatigue of CrCoNi medium-entropy alloy at room temperature

變形孿晶在CrCoNi中熵合金室溫疲勞中的作用

 

Milan Heczko?, Veronika Mazánová, Connor E. Slone, Mulaine Shih, Easo P. George, Maryam Ghazisaeidi, Jaroslav Polák, Michael J. Mills

Milan Heczko: heczko.2@osu.edu 

https://doi.org/10.1016/j.scriptamat.2021.113985

 

摘要

對表面電解拋光CrCoNi合金的圓柱形試樣進行了恒總應變幅低周疲勞試驗。合金呈現出先循環硬化后循環軟化直至失效的過程。在循環應力峰值硬化階段結束時，由擠壓物和侵入物組成的持久滑移標記(PSMs)建立了起來，這與薄的變形孿晶有關。本文設計了一個復雜的實驗流程，從被測材料的表面和塊體中提取信息。采用SEM、EBSD、ECCI、FIB和HR-STEM技術相結合，研究了循環加載初期變形孿晶的內部結構和表面形貌。此外，變形孿晶附近的局部循環塑性應變和應力集中不僅導致了早期的、發育良好的PSMs，而且導致了即使在低宏觀應力幅度下TWIP和TRIP塑性的激活。

向上滑動閱覽英文摘要

Cylindrical specimens of CrCoNi alloy with electropolished surfaces were subjected to constant total strain amplitude low cycle fatigue. The alloy exhibited an initial period of cyclic hardening followed by cyclic softening until failure occurred. At the end of hardening stage at the peak of cyclic stress, well-developed persistent slip markings (PSMs) consisting of extrusions and intrusions were associated with thin deformation twins. A sophisticated experimental workflow was designed to extract information from the surface and the bulk of tested material. A combination of SEM, EBSD, ECCI, FIB and HR-STEM was used to study the internal structure and the surface profiles around the deformation twins, which were produced during the initial period of cyclic loading. Furthermore, localized cyclic plastic strain and stress concentrations near deformation twins led not only to early, well-developed PSMs, but also to the activation of TWIP and TRIP plasticity even at low macroscopic stress amplitudes.

 

 

SCRIPTA

Vol. 202, 1 Sep. 2021, 113992

4. High strength NiMnFeCrAlCu multi-principal-element alloys with marine application perspective

高強度NiMnFeCrAlCu多主元素合金在海洋中的應用前景

 

Yidong Wu, Yuluo Li, Xuli Liu, Qinjia Wang, Xiaoming Chen, Xidong Hui?

Xidong Hui: xdhui@ustb.edu.cn  北京科技大學

https://doi.org/10.1016/j.scriptamat.2021.113992

 

摘要

鎳鋁青銅(NAB)合金是傳統的海洋材料，使用了幾十年，但面臨著強度和腐蝕性能不足的問題。在本研究中，我們開發了新型NiMnFeCrAlCu多主元素合金(MPEA)，由于其具有很強的固溶強化、耐腐蝕和抗生物結垢能力，該合金具有良好的力學性能和耐腐蝕性能。結果表明，與NBA相比，NiMnFe0.5Cr0.5Al0.2Cu1.2 MPEA具有較高的屈服強度和抗拉強度，腐蝕電流密度低1個數量級，且具有較好的銅離子釋放濃度。這些優點主要歸因于FCC+BCC雙相組織，以及Cu在FCC基體中富集和Cr在BCC晶粒中富集。這項工作對發展先進海洋材料的新戰略具有重要意義。

向上滑動閱覽英文摘要

Nickel-aluminium bronze (NAB) alloys are traditional marine materials used for decades, but face to the challenge of insufficient strength and corrosion properties. In this work, thanks to the strong solid solution strengthening, corrosion and biofouling resistant ability of multiple components, we developed novel NiMnFeCrAlCu multi-principal-element alloys (MPEAs), which exhibit excellent combination of mechanical and corrosion resistant properties. It was found that NiMnFe0.5Cr0.5Al0.2Cu1.2 MPEA has higher yield and ultimate tensile strength, and lower corrosion current density by one magnitude than those of NBA, and also shows a considerable copper ion release concentration. These merits are attributed to the dual phase of FCC+BCC, and the enrichment of Cu in the FCC matrix and Cr in the BCC grains. This work has implication in the new strategy for the development of advanced marine materials.

 

 

SCRIPTA

Vol. 202, 1 Sep. 2021, 113998

5. Vacancy surface migration mechanisms in dilute nickel-chromium alloys

稀Ni-Cr合金中的空位表面遷移機制

 

Jacob Startt, Chaitanya Deo, Rémi Dingreville?

Rémi Dingreville: rdingre@sandia.gov 

https://doi.org/10.1016/j.scriptamat.2021.113998

 

摘要

我們用第一性原理計算研究了稀Ni-Cr合金中與表面空位遷移有關的單一機制。我們調查了一套完整表面和(100)自由表面附近空位的亞表面遷移路徑，并計算了相應的遷移勢壘。結果表明，向自由表面遷移的空位會面臨較低的能壘，其通過與鄰近的Cr原子交換而不是與Ni原子交換來進行遷移。一旦一個空位到達自由表面，它就會被困在那里。結果還表明，當一個Cr原子位于自由表面下方的原子面時，導致亞表面Cr原子上方的空位的任何面內空位躍遷在能量上都是不利的。綜上所述，這些基本的單一表面遷移機制為Ni-Cr基合金表面偏析和空位遷移現象之間的復雜交互作用提供了見解。

向上滑動閱覽英文摘要

 

We investigate the unitary mechanisms related to the surface migration of vacancies in dilute Ni-Cr alloys via first-principle calculations. We survey a complete set of surface and sub-surface migration paths for vacancies near the (100) free surface and calculate the corresponding migration barriers. Our results show that a vacancy migrating towards the free surface will face lower energy barriers to migrate via atomic exchange with a neighboring Cr atom rather than with a Ni atom. Once a vacancy reaches the free surface, it will be trapped there. Our results also reveal that, when a Cr atom sits in the atomic plane just below the free surface, any in-plane vacancy hopping jump that would result in the vacancy sitting on top a subsurface Cr atom is energetically unfavorable. Taken together, these fundamental unitary surface migration mechanisms offer insights into the complex interactions between surface segregation and vacancy migration phenomena in Ni-Cr-based alloys.

 

 

SCRIPTA

Vol. 202, 1 Sep. 2021, 114004

6. Effect of alloying elements on the coarsening rate of γ? precipitates in multi-component CoNi-based superalloys with high Cr content

合金元素對高Cr多組分CoNi基高溫合金γ?析出相粗化速率的影響

 

Xiaoli Zhuang, Stoichko Antonov, Longfei Li?, Qiang Feng

Longfei Li: lilf@skl.ustb.edu.cn  北京科技大學

https://doi.org/10.1016/j.scriptamat.2021.114004

 

摘要

研究了高(14 at.%) Cr含量的多組分CoNi基高溫合金在850℃的長期時效過程中γ'的粗化行為，以及W，Mo或Ti(1 at.%)的添加對于γ/γ?微觀組織的變化、晶格錯配和元素配分行為的影響。γ'析出相的粗化行為遵循經典的Lifshitz-Slyozov-Wagner(LSW)模型，其尺寸與t1/3成比例關系。添加W，Mo或Ti（1at％）改變γ/γ'元素分配行為，從而改變γ/γ'的晶格錯配度和界面能，導致γ'析出相的粗化速率相當不同，其中Ti具有最顯著的影響。結果發現Cr是γ'粗化的速率限制元素，而不是其他合金元素。該研究可以為具有較低γ'粗化速率的CoNi基高溫合金的設計和優化提供指導。

向上滑動閱覽英文摘要

 

The γ? coarsening behavior during long-term aging at 850°C of multi-component CoNi-based superalloys with high (14 at.%) Cr content were investigated, and the effects of W, Mo or Ti (1 at.%) additions were analyzed with respect to the change in the γ/γ? microstructure, lattice misfit, and elemental partitioning behavior. The coarsening behavior of the γ? precipitates follows the classical Lifshitz-Slyozov-Wagner (LSW) model, where the size is proportional to t1/3. The addition of either W, Mo or Ti (1 at.%) alters the γ/γ? elemental partitioning behavior and thus the γ/γ? lattice misfit and interfacial energy, resulting in quite different coarsening rates of the γ? precipitates, with Ti having the most significant effect. Cr was found to be the rate-limiting element of γ? coarsening rather than the other alloying elements. This study could provide guidance for the design and optimization of CoNi-based superalloys with lower γ' coarsening rate.

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SCRIPTA

Vol. 202, 1 Sep. 2021, 114003

7. Dual plateau stress of C15-type topologically close-packed lattice structures additive-manufactured by laser powder bed fusion

通過激光粉末床熔合技術增材制造的C15型拓撲密排晶格結構的雙平臺應力

 

Xiaoyang Liu?, Asuka Suzuki, Naoki Takata, Makoto Kobashi, Masaki Kato

Xiaoyang Liu: liu.xiaoyang@e.mbox.nagoya-u.ac.jp

https://doi.org/10.1016/j.scriptamat.2021.114003

 

摘要

模擬晶體結構為設計由節點(充當原子)和支柱(充當原子鍵)的元胞構成的晶格結構提供了新的途徑。我們通過激光粉末床熔合制備了C15 Laves相(AB2型金屬間化合物)的拓撲致密(TCP)結構，在晶格結構的應力-應變曲線中發現了獨特的雙平臺區。壓縮變形晶格結構的X射線斷層掃描和有限元分析表明，兩種相對密度不同的單元的存在導致了雙平臺區。此外，C15晶格結構表現出彎曲和拉伸主導的混合變形模式，在兩種應力水平下均能吸收較高的總能量(5.0 MJ·m-3)。

向上滑動閱覽英文摘要

 

Imitating crystal structures offers new avenues to design lattice structures composed of unit cells with nodes (act as atoms) and struts (act as atomic bonds). We found out unique dual plateau regions in the stress-strain curves of lattice structures inspired by topologically close-packed (TCP) structure of C15 Laves phase (AB2-type intermetallic compounds) and manufactured via the laser powder bed fusion. X-ray computed tomography of compressively deformed lattice structures as well as finite element analysis revealed that the existence of two kinds of units with different relative density caused the dual plateau regions. In addition, the C15 lattice structures exhibited a hybrid deformation mode of bending- and stretch-dominated deformations and can absorb high total energy of 5.0 MJ·m-3 in two stress levels.

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SCRIPTA

Vol. 202, 1 Sep. 2021, 113995

8. Simultaneous deformation twinning and martensitic transformation in CoCrFeMnNi high entropy alloy at high temperatures

CoCrFeMnNi高熵合金在高溫下同時產生變形孿晶和馬氏體相變

 

S. Picak, H.C. Yilmaz, I. Karaman?

I. Karaman: ikaraman@tamu.edu 

https://doi.org/10.1016/j.scriptamat.2021.113995

 

摘要

劇烈塑性變形(SPD)可以通過晶粒細化引起材料的顯著強化，然而使用已知的SPD技術制備的材料由于低的應變硬化能力而缺乏均勻的塑性變形。本研究利用等通道轉角擠壓(ECAP)處理在高溫下同時激活CoCrFeMnNi高熵合金(HEA)的孿晶誘導(TWIP)和相變誘導塑性(TRIP)，這是首次報道的高溫異常現象。透射電鏡和電子背散射衍射分析揭示了顯微結構特征。在室溫拉伸實驗中，相變區和孿晶區以及晶粒細化產生了高強度(~1 GPa)和均勻的塑性變形能力。TWIP/TRIP的出現歸因于ECAP處理過程中的高強度水平和目前HEA相對較低的層錯能。

向上滑動閱覽英文摘要

 

Severe plastic deformation (SPD) leads to substantial strengthening in materials via grain refinement, however, the main drawback of the materials processed using known SPD techniques is the lack of uniform plastic deformation due to low strain hardening capability. In this study, equal channel angular pressing (ECAP) at high temperatures was utilized to activate simultaneous twinning-induced (TWIP) and transformation-induced plasticity (TRIP) in the CoCrFeMnNi high entropy alloy (HEA), which are anomalous at high temperatures and reported for the first time. Transmission electron microscopy and electron backscattered diffraction analysis were performed to reveal microstructural features. The presence of the transformed and twinned regions as well as grain refinement in this alloy yielded a high strength level (around 1 GPa) with uniform plastic deformation ability in room temperature tension experiments. The observation of TWIP/TRIP was attributed to high strength levels applied via ECAP and relatively low stacking fault energy of the present HEA.

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