Qingqing Ding
Zhejiang University
Ultimate tensile strengthLattice (order)CrystalliteTransmission electron microscopyPhase transitionCreepDislocationComposite materialMaterials scienceScanning transmission electron microscopyDeformation mechanismSuperalloyCondensed matter physicsAlloyPhase (matter)Dark field microscopySlip (materials science)Amorphous solidSingle crystalDendrite (crystal)CrystallographyMicrostructure
20Publications
9H-index
1,494Citations
Publications 20
Newest
#1Wanshun Xia (ZJU: Zhejiang University)H-Index: 2
#2Xinbao Zhao (ZJU: Zhejiang University)H-Index: 4
Last. Ze Zhang (ZJU: Zhejiang University)H-Index: 77
view all 8 authors...
Abstract The creep inconsistency between dendrite core and interdendritic region is investigated in a nickel-based single crystal superalloy under 1373 K and 137 MPa. Two specimens with higher and lower degree of elemental inhomogeneity on dendritic structures are compared. For specimen with higher inhomogeneity, stronger segregation of refractory elements reinforces the local strength in dendrite core, but damages the strength in interdendritic region. Creep strain is accumulated faster in inte...
Source
#1Qingqing Ding (ZJU: Zhejiang University)H-Index: 9
#2Hongbin Bei (ZJU: Zhejiang University)H-Index: 62
Last. Ze Zhang (ZJU: Zhejiang University)H-Index: 77
view all 7 authors...
Source
Abstract The GH3536 (Hastelloy X) superalloy is one of the most widely used Ni-based sheet alloys for gas turbine hot parts. In order to investigate its relationship among the processing, microstructure, and mechanical properties, GH3536 alloy was fabricated from pure constituent elements by arc melting and drop casting. The drop-cast ingots were homogenized, cold rolled and recrystallized to obtain single phase microstructure with average grain size of ∼ 12 μm. Tensile tests were then performed...
5 CitationsSource
#1Qingqing DingH-Index: 9
#2Hongbin BeiH-Index: 62
Last. Ze ZhangH-Index: 77
view all 7 authors...
3 CitationsSource
#1Wanshun Xia (ZJU: Zhejiang University)H-Index: 2
#2Xinbao Zhao (ZJU: Zhejiang University)H-Index: 4
Last. Ze Zhang (ZJU: Zhejiang University)H-Index: 3
view all 8 authors...
Abstract The chemical and structural evolution within dislocation networks are investigated in a nickel-based single crystal superalloy crept under 1373K and 137MPa. The local region within dislocation networks can be divided to two separated parts: gridlines which compose the arrangements of dislocation networks and mesh regions as intervals between gridlines. With evolution of dislocation networks, precipitation of nano-sized γ′ phase (γ′n) are observed in mesh region, while gridlines always d...
1 CitationsSource
#1Qingqing DingH-Index: 9
#2Hongbin BeiH-Index: 62
Last. Ze ZhangH-Index: 77
view all 5 authors...
A second-generation Ni-based superalloy has been directionally solidified by using a Bridgman method, and the key processing steps have been investigated with a focus on their effects on microstructure evolution and mechanical properties. The as-grown microstructure is of a typical dendrite structure with microscopic elemental segregation during solidification. Based on the microstructural evidence and the measured phase transformation temperatures, a step-wise solution treatment procedure is de...
5 CitationsSource
#1Qingqing Ding (ZJU: Zhejiang University)H-Index: 9
#2Lao Zhezhu (ZJU: Zhejiang University)H-Index: 1
Last. Ze Zhang (ZJU: Zhejiang University)H-Index: 77
view all 6 authors...
Abstract L12 structured γ′ phase is the main strengthening phase of Ni-base superalloys, which contain multiple alloying elements. Locations of these elements in the lattice are crucial for understanding the mechanical/physical properties of γ′ phases. Here, we reveal the site occupancy of various elements in γ′ phases of two multi-component Ni-base single crystal superalloys by using advanced scanning transmission electron microscopy and energy disperse spectroscopy. Cr, Mo, Re, Ta, W and Ti at...
5 CitationsSource
High-entropy alloys are a class of materials that contain five or more elements in near-equiatomic proportions1,2. Their unconventional compositions and chemical structures hold promise for achieving unprecedented combinations of mechanical properties3–8. Rational design of such alloys hinges on an understanding of the composition–structure–property relationships in a near-infinite compositional space9,10. Here we use atomic-resolution chemical mapping to reveal the element distribution of the w...
278 CitationsSource
#1Qingqing Ding (ZJU: Zhejiang University)H-Index: 9
#2Xiaoqian Fu (ZJU: Zhejiang University)H-Index: 5
Last. Robert O. Ritchie (University of California, Berkeley)H-Index: 132
view all 11 authors...
Abstract Technologically important mechanical properties of engineering materials often degrade at low temperatures. One class of materials that defy this trend are CrCoNi-based medium- and high-entropy alloys, as they display enhanced strength, ductility, and toughness with decreasing temperature. Here we show, using in situ straining in the transmission electron microscope at 93 K (−180 °C) that their exceptional damage tolerance involves a synergy of deformation mechanisms, including twinning...
55 CitationsSource
#1Xiaolan Xue (NU: Nanjing University)H-Index: 11
#2Renpeng Chen (NU: Nanjing University)H-Index: 31
Last. Zhong Jin (NU: Nanjing University)H-Index: 68
view all 13 authors...
The catalytic conversion of nitrogen to ammonia is one of the most important processes in nature and chemical industry. However, the traditional Haber-Bosch process of ammonia synthesis consumes substantial energy and emits a large amount of carbon dioxide. Solar-driven nitrogen fixation holds great promise for the reduction of energy consumption and environmental pollution. On the basis of both experimental results and density functional theory calculations, here we report that the oxygen vacan...
153 CitationsSource