Results 21 to 30 of about 197,455 (212)
ErB4 and NdB4 nanostructured powders are produced by mechanochemical synthesis. 5 h mechanical alloying and 4 M HCl acid leaching are used in the production. ErB4 and NdB4 powders exhibit maximum magnetization of 0.4726 emu g−1 accompanied with an antiferromagnetic‐to‐paramagnetic phase transition at about TN = 18 K and 0.132 emu g−1 with a maximum at ...
Burçak Boztemur +5 more
wiley +1 more source
Phase Field Failure Modeling: Brittle‐Ductile Dual‐Phase Microstructures under Compressive Loading
The approach by Amor and the approach by Miehe and Zhang for asymmetric damage behavior in the phase field method for fracture are compared regarding their fitness for microcrack‐based failure modeling. The comparison is performed for the case of a dual‐phase microstructure with a brittle and a ductile constituent.
Jakob Huber, Jan Torgersen, Ewald Werner
wiley +1 more source
Accurate Calculation Method for Mechanical Specific Energy of Horizontal Well
The existing drilling efficiency-monitoring model based on the theory of mechanical specific energy is only applicable to vertical wells. When it is used to monitor the drilling efficiency of horizontal wells, the impact of high friction in horizontal ...
Shuangshuang Wang, Qian Li
semanticscholar +1 more source
Time‐Dependent Oxidation and Scale Evolution of a Wrought Co/Ni‐Based Superalloy
This study shows how a new wrought Co/Ni‐based superalloy resists oxidation at 800 ∘$^\circ$C. The oxide scale changes from rough, fast‐growing spinel to a dense, protective chromia–alumina layer. Atom probe analysis reveals tiny refractory‐rich bubbles at the interface that mark the transition to long‐term, diffusion‐controlled protection ...
Cameron Crabb +6 more
wiley +1 more source
Calculation and Experimental Study on a Rotary Percussion Positive Displacement Motor
A positive displacement motor (PDM) driven rotary percussion drilling tool, named rotary percussion PDM (RP PDM), is developed. Using conventional PDM as rotating power source, high-frequency axial impact and vibration or impact is generated to raise ...
Haiping Zhang, Y. Zang, Jiachang Wang
semanticscholar +1 more source
Do not let thermal drift and instrument artifacts deceive high‐temperature nanoindentation results. We compare classical Oliver–Pharr and automatic image recognition analyses across steels and a Ni alloy to quantify these effects. Accounting for artifacts reveals systematic softening with temperature, while Cr and Ni additions boost resistance ...
Velislava Yonkova +2 more
wiley +1 more source
Structural Design and Test of Mechanical Rotary Percussion Drilling Tool
Rotary percussion drilling technology can greatly increase the ROP of hard formations, but for plastic rocks, rock fragmentation is poor. For this reason, this paper proposes a technical plan for mechanical rotary percussion drilling tool prototype ...
Zhang Haiping
doaj
Manufacturing problems such as heat treatment‐induced cracking hinder the widespread application of the laser powder bed fusion (LPBF) process to superalloys. In this study, cracks in the LPBF components of Inconel 738LC superalloy are characterized after heat treatment at various temperature ranges, revealing two distinct cracking behaviors.
Kosuke Kuwabara +4 more
wiley +1 more source
In situ synchrotron high‐energy X‐ray diffraction reveals the real‐time high‐temperature phase evolution of a ternary V‐9Si‐6.5B alloy. The study uncovers a kinetically delayed V5SiB2 → V8SiB4 transformation governed by massive structural and chemical barriers.
Zahra Sabeti +4 more
wiley +1 more source
Simulation Study on the Drilling of PDC Bit at Compound Drilling Condition
The forces on the PDC bit at the bottomhole could impact the PDC bit drilling efficiency and cutter wear.The cutter-rock interactions could be more complex in compound drilling mode.A new PDC bit drilling simulation method for compound drilling based on ...
Zheng Jiawei +5 more
doaj

