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金属顶刊双语导读丨Scripta Mater. Vol.204, 1 Nov. 2021（下）

2021-08-29 来源：Goal Science

 

本期包含金属材料领域论文11篇，涵盖了高熵合金、马氏体等，国内科研单位包括中南大学、合肥固体物理研究所、南京理工大学等（通讯作者单位）。

 

Vol. 204 目录

1. Studies of Cu-Sn interdiffusion coefficients in Cu3Sn and Cu6Sn5 based on the growth kinetics

基于生长动力学的Cu3Sn和Cu6Sn5中Cu-Sn相互扩散系数的研究

 

2. Hydrogen-induced transgranular to intergranular fracture transition in bi-crystalline nickel

双晶镍中氢致穿晶向晶间断裂转变

 

3. Short-range ordering governs brittleness and ductility in W-Ta solid solution: Insights from Pugh's shear-to-bulk modulus ratio

W-Ta固溶体中的短程有序控制脆性和延展性：来自Pugh的剪切体积模量比的见解

 

4. Multicomponent Ni-rich high-entropy alloy toughened with irregular-shaped precipitates and serrated grain boundaries

具有不规则形状析出物和锯齿状晶界的多组元富镍高熵合金

 

5. Role of thermo-mechanical gyrations on the α/β interface stability in a Ti6Al4V AM alloy

热机械旋转对Ti6Al4V AM合金中α/β界面稳定性的影响

 

6. Grain boundary relaxation behavior and phase stability of AlCrTiVx (x = 0, 0.5 and 1) high-entropy alloys

AlCrTiVx (x = 0, 0.5 and 1)高熵合金的晶界弛豫行为和相稳定性

 

7. New mechanism and criterion for forming multi-component solid-solution alloys

形成多组元固溶体合金的新机制和判据

 

8. 5M and 7M martensitic stability and associated physical properties in Ni50Mn35In15 alloy: first-principles calculations and experimental verification

Ni50Mn35In15合金的5M和7M马氏体稳定性及相关物理性能：第一性原理计算和实验验证

 

9. Revealing tribo–oxidation mechanisms of the copper–WC system under high tribological loading

揭示高摩擦载荷下Cu-WC系统的摩擦氧化机制

 

10. Machine learning to predict aluminum segregation to magnesium grain boundaries

机器学习预测铝在镁晶界的偏析

 

11. In-situ TEM observation and MD simulation of the reaction and transformation of <100> loops in tungsten during H2+ & He+ dual-beam irradiation

H2+和He+双光束辐照过程中钨<100>环反应和转变的原位TEM观察和MD模拟

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114138

1. Studies of Cu-Sn interdiffusion coefficients in Cu3Sn and Cu6Sn5 based on the growth kinetics

基于生长动力学的Cu3Sn和Cu6Sn5中Cu-Sn相互扩散系数的研究

 

Yue Wang, Xianwen Peng, Jihua Huang✉, Zheng Ye, Jian Yang, Shuhai Chen

Jihua Huang: jhhuang62@sina.com 北京科技大学

https://doi.org/10.1016/j.scriptamat.2021.114138

 

摘要

在这项工作中，我们基于反应/扩散理论建立了Cu3Sn（ε）和Cu6Sn5（η）生长的动力学模型。基于Cu和Sn原子的相互扩散控制生长的理论，建立了ε和η层生长的动力学方程。 在考虑和不考虑相变引起的体积变化的两种情况下推导了动力学方程，其中Cu-Sn相互扩散系数（, ）都被列为主要因素。在此基础上，测定了两种条件下在130～200℃范围内的互扩散系数，结果表明在某种程度上体积变化影响了和的计算精度。

向上滑动阅览英文摘要

In this work, we set up a kinetic model of Cu3Sn (ε) and Cu6Sn5 (η) growth based on the reaction/diffusion theory. The kinetic equations of the ε and η layers growth were established according to the principle that the growth was controlled by the interdiffusion of Cu and Sn atoms. We derived the kinetic equations with and without consideration of the volume change caused by phase transitions, where the Cu-Sn interdiffusion coefficients (, ) were all included as dominant factors. On this basis, the interdiffusion coefficients at 130 ~ 200 °C were determined under the two conditions, and results showed that the volume change affected the accuracy of the calculation of  and  to some extent.

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114122

2. Hydrogen-induced transgranular to intergranular fracture transition in bi-crystalline nickel

双晶镍中氢致穿晶向晶间断裂转变

 

Yu Ding, Haiyang Yu, Kai Zhao, Meichao Lin, Senbo Xiao, Michael Ortiz, Jianying He,

Zhiliang Zhang✉

Zhiliang Zhang: zhiliang.zhang@ntnu.no

https://doi.org/10.1016/j.scriptamat.2021.114122

 

摘要

众所周知，氢会影响金属材料的位错塑性和断裂模式。然而，氢与晶界之间的纳米级相互作用机制在很大程度上仍然不清晰。通过对具有Σ5(210)[001]晶界的双晶Ni进行单轴应变，原子模型阐明了由氢促进的穿晶到晶间断裂转变，并揭示了特定的氢控制塑性机制。研究发现氢在晶界附近形成局部气氛，这会引起局部应力集中并抑制随后在变形过程中晶界处的应力松弛。正是这种局部应力集中促进了位错更早的发展、孪晶演化和更多空位的产生，从而促进了纳米空隙。与无氢样品的穿晶断裂相反，纳米空隙的成核和生长最终导致晶界处的晶间断裂。

向上滑动阅览英文摘要

It is known that hydrogen can influence the dislocation plasticity and fracture mode transition of metallic materials, however, the nanoscale interaction mechanism between hydrogen and grain boundary largely remains illusive. By uniaxial straining of bi-crystalline Ni with a Σ5(210)[001] grain boundary, a transgranular to intergranular fracture transition facilitated by hydrogen is elucidated by atomistic modeling, and a specific hydrogen-controlled plasticity mechanism is revealed. Hydrogen is found to form a local atmosphere in the vicinity of grain boundary, which induces a local stress concentration and inhibits the subsequent stress relaxation at the grain boundary during deformation. It is this local stress concentration that promotes earlier dislocation emission, twinning evolution, and generation of more vacancies that facilitate nanovoiding. The nucleation and growth of nanovoids finally leads to intergranular fracture at the grain boundary, in contrast to the transgranular fracture of hydrogen-free sample.

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114136

3. Short-range ordering governs brittleness and ductility in W-Ta solid solution: Insights from Pugh's shear-to-bulk modulus ratio

W-Ta固溶体中的短程有序控制脆性和延展性：来自Pugh的剪切体积模量比的见解

 

Honggang Liu, Sai Tang, YunZhu Ma, Wensheng Liu, Chaoping Liang✉

Chaoping Liang: cpliang@csu.edu.cn 中南大学

https://doi.org/10.1016/j.scriptamat.2021.114136

 

摘要

在这项工作中，通过第一性原理计算研究了W-Ta固溶体中，从Pugh的剪切体积模量（G/B）比推导出的短程有序对固有脆性和延展性的影响。结果表明，作为脆性指标的G/B值随W-Ta固溶体中Ta浓度的降低而降低。依据G/B值，与理想固溶体和原子偏析结构相比，短程有序结构表现出延展性。这种短程有序结构的延展性源于部分共价W-W键数量的减少和W-Ta固溶体中W-W相互作用的中心对称屏蔽。研究结果表明，短程有序化应该在W固溶体中的固溶软化和辐照硬化现象中起一定作用，这可以用于未来的W合金设计。

向上滑动阅览英文摘要

In this work, the effect of short-range ordering on the intrinsic brittleness and ductility deduced from Pugh's shear-to-bulk modulus (G/B) ratio in W-Ta solid solution is investigated by first-principles calculation. The results show that the G/B value, an indicator of brittleness, decreases as a function of Ta concentration in W-Ta solid solution. The short-range ordered structure displays a ductile behavior in comparison to ideal solid solution and atomic segregated structure in terms of G/B value. This ductility of short-range ordered structure originates from the reduction of the number of partially covalent W-W bonds and a centrosymmetric screening of W-W interactions in W-Ta solid solution. Our findings suggest that short-range ordering should play a role in the solid solution softening and irradiation hardening phenomenon in W solid solution, and could be included in the future design of ductile W alloys.

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114066

4. Multicomponent Ni-rich high-entropy alloy toughened with irregular-shaped precipitates and serrated grain boundaries

具有不规则形状析出物和锯齿状晶界的多组元富镍高熵合金

 

S.W. Wu, T. Yang, B.X. Cao, J.H. Luan, Y.F. Jia, L. Xu, Y.K. Mu, T.L. Zhang, H.J. Kong,

X. Tong, J.C. Peng, G. Wang, Q.J. Zhai, J. Lu, C.T. Liu✉

C.T. Liu: chainliu@cityu.edu.hk 深圳福田研究所

https://doi.org/10.1016/j.scriptamat.2021.114066

 

摘要

一种新型的沉淀强化多元富镍Ni46.23Co23Cr10Fe5Al8.5Ti4W2Mo1C0.15B0.1Zr0.02 (at.%) 高熵合金（HEA），设计其在1000°C屈服后发生应变硬化而不是应变软化。由于晶间开裂的快速发生，具有球形析出物和垂直晶界的HEA很脆，抗拉强度约220 MPa，均匀伸长率仅为约1.9%。锯齿状晶界结构有效地克服了这种晶间开裂问题。该HEA具有不规则形状的沉淀物和锯齿状的晶界，使其显示出脆性到韧性的转变，具有高达~260 MPa的优异强度和~6.5% 的均匀延伸率。强度和延展性的提高归因于锯齿状晶界对晶间裂纹形核和扩展的抵抗力增强。该研究结果为具有优异机械性能的高温结构材料的创新设计提供了一种新方法。

向上滑动阅览英文摘要

A novel precipitation-strengthened multicomponent Ni-rich Ni46.23Co23Cr10Fe5Al8.5Ti4W2Mo1C0.15B0.1Zr0.02 (at.%) high-entropy alloy (HEA) was designed with strain-hardening after yielding rather than strain-softening even at the temperature of 1000°C. Due to the rapid onset of intergranular cracking, the HEA with spherical precipitates and straight grain boundaries was brittle, exhibiting an inferior tensile strength of ~220 MPa, and an insufficient uniform elongation of only ~1.9%. The serrated-grain-boundary architecture effectively overcomes this intergranular cracking issue. The resultant HEA with irregular-shaped precipitates and serrated grain boundaries showed a brittle-to-ductile transition, giving in a superior strength up to as high as ~260 MPa while maintaining a uniform elongation of ~6.5%. Such an improvement of the strength and ductility has been attributed to the enhanced resistance of the serrated grain boundaries to the intergranular crack nucleation and propagation. Our current results provide a new method for the innovative design of high-temperature structural materials with superior mechanical performances.

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114134

5. Role of thermo-mechanical gyrations on the α/β interface stability in a Ti6Al4V AM alloy

热机械旋转对Ti6Al4V AM合金中α/β界面稳定性的影响

 

Sabina Kumar✉, Sri Ram Vijayan, Peeyush Nandwana, Jonathan D. Poplawsky, Chen Yan,

Sudaranam Suresh Babu

Sabina Kumar: skumar17@vols.utk.edu

https://doi.org/10.1016/j.scriptamat.2021.114134

 

摘要

增材制造过程中经历的能量波动会导致零件内空间和时间瞬变的演变。一般来说，在制造过程中对这些瞬变的原位监测几乎是不可能的。为了深入了解这些局部热机械瞬变对界面稳定性的影响，在AM Ti6Al4V合金上施加具有已知边界条件的快速热机械反转，这会导致相变从而增加β相稳定性。这项研究的目标是，通过由于塑性应变积累和扩散动力学而产生的储存能量的概念来理解这种相变的动力学。原子探针断层扫描用于研究跨界面的溶质元素的分配。正如预期的那样，经历热机械循环的样品的整个β相中显示出较低的钒浓度。整个界面的浓度分布以及全宽半分析提供了对受热机械旋转影响的α → β转变所涉及的潜在相变动力学的深入了解。

向上滑动阅览英文摘要

Fluctuating energy distributions experienced during Additive Manufacturing yield an evolution of spatial and temporal transients within a part. In general, the in-situ monitoring of these transients is near to impossible during manufacturing. In order to then gain perspective into the impact on these localized thermo-mechanical transients on the interface stability, rapid thermo-mechanical reversals with known boundary conditions are imposed on an AM Ti6Al4V alloy which resulted in a phase transformation leading to an increased β phase stability. Our goal with this study is to comprehend the kinetics of this phase transformation with concepts of stored energy due to plastic strain accumulation and diffusion kinetics. Atom Probe Tomography is employed to study the partitioning of the solute elements across the interface. As expected, the thermo-mechanically cycled samples showed a reduced Vanadium concentration across the β phase. This concentration profile across the interface, alongside a full-width-half-max analysis, provided insight on the potential phase transformation kinetics involved in the α → β transformation subject to thermo- mechanical gyrations.

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114144

6. Grain boundary relaxation behavior and phase stability of AlCrTiVx (x = 0, 0.5 and 1) high-entropy alloys

AlCrTiVx (x = 0, 0.5 and 1)高熵合金的晶界弛豫行为和相稳定性

 

Meng Sun✉, Xueqing Liu, Weibin Jiang, Yawei Lei, Jianggang Ke, Rui Liu, Xianping

Wang✉, Xuebang Wu, Qianfeng Fang✉, Changsong Liu

Meng Sun: mengsun@issp.ac.cn 合肥固体物理研究所

Xianping Wang: xpwang@issp.ac.cn 合肥固体物理研究所

Qianfeng Fang: qffang@issp.ac.cn 合肥固体物理研究所

https://doi.org/10.1016/j.scriptamat.2021.114144

 

摘要

本文报道了AlCrTiVx（x = 0、0.5 和 1）高熵合金的缺陷弛豫行为。在所有样品中都观察到明显的内摩擦（IF）峰叠加在单调增加的高温背景（HTBG）上，这归因于晶界峰。晶界弛豫的活化能随着V含量的增加而增加，这意味着随着混合熵的增加，原子扩散的复杂性和难度增加。在1100 °C退火5 h后，AlCrTiV合金的HTBG异常增加。微观结构分析证实，这是由于纳米富钛相的析出引起的错配位错的出现。这些发现可能为评估和设计具有高热稳定性的高熵合金提供新的自由度。

向上滑动阅览英文摘要

The defect relaxation behavior of AlCrTiVx (x = 0, 0.5, and 1) high entropy alloys was reported in this paper. A pronounced internal friction (IF) peak superimposing on a monotonously increasing high-temperature background (HTBG) was observed in all samples, which was ascribed to grain boundary peak. The activation energy of grain boundary relaxation increases with the increasing V content, implying an increasing complexity and difficulty of atomic diffusion with the increasing mixing entropy. After annealing at 1100 °C for 5 h, the HTBG of AlCrTiV alloy abnormally increases, which was attributed to the appearance of misfit dislocations induced by precipitation of nano-sized Ti-rich phases as confirmed by microstructure analysis. These findings may provide a new degree of freedom for evaluating and designing high entropy alloys with high thermal stability.

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114128

7. New mechanism and criterion for forming multi-component solid-solution alloys

形成多组元固溶体合金的新机制和判据

 

Tsang-Tse Fang✉

Tsang-Tse Fang: ttfang@mail.ncku.edu.tw

https://doi.org/10.1016/j.scriptamat.2021.114128

 

摘要

评估了形成单相多组元固溶体合金（MCSSAs）的一些现有标准，并提出了基于原子堆积拓扑的新标准。提出了一种关于MCSSAs发展的新机制，其中，表面层的多组分效应降低纳米晶核的表面自由能，起着重要的作用。对不同温度退火的CoCrFeMnNi合金的相稳定性提供了更合理的解释。

向上滑动阅览英文摘要

Some existing criteria for forming single-phase multicomponent solid-solution alloys (MCSSAs) are assessed, and a new criterion based on the topology of atomic packing is propounded. A new mechanism concerning the development of MCSSAs is posited, where the multicomponent effect in surface layer, reducing the surface free energy of nanocrystalline nucleus, plays a significant role. More reasonable interpretation regarding the phase stability of CoCrFeMnNi alloy annealed at different temperatures is provided.

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114140

8. 5M and 7M martensitic stability and associated physical properties in Ni50Mn35In15 alloy: first-principles calculations and experimental verification

Ni50Mn35In15合金的5M和7M马氏体稳定性及相关物理性能：第一性原理计算和实验验证

 

Xinzeng Liang, Xinjun Jiang, Jianglong Gu, Jing Bai✉, Ziqi Guan, Zhenzhuang Li, Haile

Yan, Yudong Zhang, Claude Esling, Xiang Zhao✉, Liang Zuo

Jing Bai: baijing@neuq.edu.cn 东北大学，东北大学秦皇岛分校

Xiang Zhao: zhaox@mail.neu.edu.cn 东北大学

https://doi.org/10.1016/j.scriptamat.2021.114140

 

摘要

Ni-Mn基铁磁形状记忆合金优异的磁驱动性能本质上与调制马氏体的存在有关。 然而，调制马氏体的亚稳定性阻碍了这些特性的可用性。在此，通过第一性原理计算和实验研究了 Ni50Mn35In15合金中5M和7M调制马氏体的相稳定性和相关物理性能。结果表明，该合金经历了磁结构耦合转变（即铁磁奥氏体→亚铁磁5M马氏体→铁磁7M马氏体）。基于状态密度和微分电荷密度分析，可理解可能相的稳定性。7M马氏体中Ni和Mn原子之间的强键合能力使其成为最稳定的相。

向上滑动阅览英文摘要

The excellent magnetic-driven properties of Ni-Mn-based ferromagnetic shape memory alloys are intrinsically related to the presence of the modulated martensite; however, the metastability of modulated martensite hinders the availability of these properties. Herein, the phase stability and associated physical properties of the 5M and 7M modulated martensites in Ni50Mn35In15 alloy are studied by the first-principles calculations and experiments. Results show that this alloy undergoes a magneto-structural coupling transformation (i.e., ferromagnetic austenite → ferrimagneitc 5M martensite → ferromagnetic 7M martensite). The stability of the possible phases can be understood based on both the density of states and differential charge densities analysis. A strong bonding ability between Ni and Mn atoms in the 7M martensite is responsible for it being the most stable phase.

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114142

9. Revealing tribo–oxidation mechanisms of the copper–WC system under high tribological loading

揭示高摩擦载荷下Cu-WC系统的摩擦氧化机制

 

X. Chen✉, Y. Ma✉, Y. Yang, A. Meng, Z.X. Han, Z. Han, Y.H. Zhao✉

X. Chen: xiang.chen@njust.edu.cn 南京理工大学

Y. Ma: y.ma@mpie.de

Y.H. Zhao: yhzhao@njust.edu.cn 南京理工大学

https://doi.org/10.1016/j.scriptamat.2021.114142

 

摘要

在高摩擦载荷期间，研究了纯铜相对于碳化钨（WC）球体的近表面结构和化学变化。 在Cu-WC摩擦系统中确定了基本阶段：(i)在最初阶段，高摩擦应力促进了晶粒细化到超细晶粒状态；(ii)极细（~3 nm）富氧铜纳米颗粒在近表层中的成核和氧化铜随后的生长；(iii)具有异质Cu和O分布的连续纳米结构混合层在后期的形成。近表面机械混合可能是高摩擦载荷下化学改性的主要原因。该发现为复杂的摩擦化学修饰提供了原子解释，这是面向材料的摩擦学中最有趣的现象之一。

向上滑动阅览英文摘要

The near-surface structural and chemical changes were investigated for pure copper against a tungsten carbide (WC) sphere during high tribological loading. Fundamental stages are identified in the Cu-WC tribo-system: (i) high tribological stress promotes grain refinement to the ultra-fine grains regime in the very beginning; (ii) nucleation of extremely fine (~3 nm) oxygen–enriched Cu nano particles in the near-surface layer and subsequent growth of the Cu2O oxide; (iii) formation of continuous nanostructured mixing layer with heterogeneous Cu and O distribution in the late stage. Near-surface mechanical mixing is presumably the main contribution to chemical modifications under high tribological loading. Our findings shed atomic-insights into intricate tribochemical modifications, one of the most intriguing phenomena in material-oriented tribology.

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114150

10. Machine learning to predict aluminum segregation to magnesium grain boundaries

机器学习预测铝在镁晶界的偏析

 

Joseph Messina, Renjie Luo, Ke Xu, Guanghong Lu, Huiqiu Deng, Mark A Tschopp, Fei

Gao✉

Fei Gao: eigaoum@umich.edu

https://doi.org/10.1016/j.scriptamat.2021.114150

 

摘要

镁合金由于其高的强度重量比而成为许多应用的优质候选材料，但其他性能如耐腐蚀性、可成形性和蠕变仍是问题。在镁铝合金中，Mg17Al12相在晶界（GBs）析出会对机械性能和腐蚀行为产生重要影响。为了更好地理解这些影响，必须首先评估铝对GB的原子偏析的作用。本研究使用原子模拟来量化铝偏析能，以训练机器学习模型。铝原子被反复放置在近30个不同的镁对称倾斜晶界（STGB）的原子位置。结果显示了铝偏析如何受GB结构和局部原子环境的影响。使用机器学习技术计算感兴趣的晶界物理特性可以对晶界科学和工程领域产生广泛的影响。

向上滑动阅览英文摘要

Magnesium alloys are good candidates for a number of applications due to their high strength-to-weight ratio, but other properties like corrosion resistance, formability, and creep are still a concern. In magnesium-aluminum alloys, Mg17Al12 phase precipitates at the grain boundaries (GBs) can have important implications on the mechanical and corrosion behavior. In order to better understand the effects, atomistic segregation of aluminum to GBs must be evaluated first. This study uses atomistic simulations to quantify aluminum segregation energetics for training a machine learning model. Aluminum atoms were iteratively placed at various atomic sites near 30 different symmetric tilt grain boundaries (STGBs) in magnesium. The results show how aluminum segregation is affected by GB structure and the local atomic environment. The ability to compute grain boundary physical properties of interest using machine learning techniques can have broad implications for the area of grain boundary science and engineering.

 

 

SCRIPTA

Vol. 204, 1 Nov. 2021, 114154

11. In-situ TEM observation and MD simulation of the reaction and transformation of <100> loops in tungsten during H2+ & He+ dual-beam irradiation

H2+和He+双光束辐照过程中钨<100>环反应和转变的原位TEM观察和MD模拟

 

Yifan Ding, Long Guo, Yipeng Li, Xinyi Liu, Guang Ran✉, Lu Wu, Xi Qiu, Huiqiu Deng,

Xiaoyong Wu, Yuanming Li, Xiuyin Huang

Guang Ran: gran@xmu.edu.cn 厦门大学，福建核工程研究中心

https://doi.org/10.1016/j.scriptamat.2021.114154

 

摘要

低迁移率<100>环显著影响体心立方材料的力学性能，其产生和演化是近年来的研究热点。然而，对于后续辐照过程中形成的<100>环的反应仍然缺乏直接观察，这阻碍了更好地理解辐照引起的机械性能退化。在这里，我们首次报道了钨30 keV H2+和He+双光束照射期间，通过原位TEM观察到了<100>环之间的反应产生了1/2<111>环。分子动力学模拟表明，该反应需要初始<100>环的合适位置和高温，以诱导<100>环分裂成1/2<111>段，然后转化为1/2<111>环。同时，原位观察到<100>环的演变，<100>环的平均尺寸和面数密度被量化为辐射通量的函数。

向上滑动阅览英文摘要

Low mobility <100> loops significantly affect the mechanical properties of body-centered cubic materials and their generation and evolution have been a hot research topic recently. However, there is still a lack of direct observation on the reaction of the formed <100> loops during subsequent irradiation, which hinders a better understanding of the degradation of mechanical properties induced by irradiation. Here, we reported for the first time that the reaction between <100> loops produced 1/2<111> loop through in-situ TEM observation during 30 keV H2+ & He+ dual-beam irradiation in tungsten. Molecular dynamics simulation showed that this reaction required appropriate relative position of the initial <100> loops and high temperature that could induce <100> loop split into 1/2<111> segments and then transformed into 1/2<111> loop. Meanwhile, the evolution of <100> loops was in-situ observed. The average size and areal number density of <100> loops were quantified as a function of irradiation fluence.