In support of NASA's Triton Hopper project, mechanical response data for solid nitrogen are needed for concept validation and development. Available mechanical properties data is sparse with only three known indentation measurements existing between 30 and 40 K. To generate more data, a custom instrumented hardness tester was developed to interface with a cryostat. The system was used to conduct cylindrical punch indentation testing at Triton-relevant thermodynamic conditions. Pressure versus displacement curves and hardness values were obtained. In the experiments the hardness ranged between about 2 kg/mm and 0.5 kg/mm in the aforementioned temperature range. A suspected brittle fracture is observed at lower temperatures in the range.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7709784 | PMC |
| http://dx.doi.org/10.1016/j.cryogenics.2020.103191 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
assessment of push-out bond strength of cold ceramic and mineral trioxide aggregate to root dentin.
Dent Res J (Isfahan)
July 2024
Department of Endodontics, Dental School, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Background: To provide a continuous seal of the root canal, root-filling material should bond to the root canal dentin, ensuring the integrity of both the root-filling material and dentin remains in a static and functional state. The present study assessed the push-out bond strength of mineral trioxide aggregate (MTA) and cold ceramic (CC).
Materials And Methods: In this laboratory trial study, 20 single-rooted, extracted human teeth without caries and cracks were selected.
A Study on Yield Criteria Influence on Anisotropic Behavior and Fracture Prediction in Deep Drawing SECC Steel Cylindrical Cups.
Materials (Basel)
June 2024
Innovative Global Program, Shibaura Institute of Technology, Tokyo 135-8548, Japan.
The deep drawing process, a pivotal technique in sheet metal forming, frequently encounters challenges such as anisotropy-induced defects. This study comprehensively investigates the influence of various yield criteria on the anisotropic behavior and fracture prediction in SECC steel cylindrical cups. It integrates Hill'48R, Hill'48S, and von Mises yield criteria in conjunction with Swift's hardening law to evaluate material behavior under complex stress states.
View Article and Find Full Text PDFFinite Element Simulation of Punch Structure and Its Effect on Microstructure Evolution of Mg-Gd-Y-Zn-Zr Alloy via Rotary Extrusion Method.
Materials (Basel)
July 2022
College of Materials Science and Engineering, North University of China, Taiyuan 030051, China.
This article aims to explore the impact of the punch structure (number of grooves, area ratio of grooves, depth of grooves and flaring angle) on the loading, torque and metal flow during the rotary extrusion (RE) process via finite element simulation (FEM) software. In order to further verify the simulation results, physical experiments were carried out and the microstructure of Mg-Gd-Y-Zn-Zr alloy after RE deformation was characterized and analyzed. The FEM results indicated that increasing the groove number will increase the amount of shear deformation and promote the metal at the bottom of the punch to flow rapidly to the cylinder wall.
View Article and Find Full Text PDFFirst Report of a New Postharvest Disease of Pear Fruit Caused by Ceratocystis fimbriata in Kunming, China.
Plant Dis
May 2022
State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural UniversityKunming, China, 650201;
Article Synopsis
- Pears, specifically Pyrus pyrifolia, are important to the Chinese economy, and instances of brown rot were discovered in Kunming's farmer market during autumn 2016, affecting 2% to 5% of the harvested fruits.
- Researchers isolated the pathogen responsible for brown rot using carrot baiting, transferring ascospores onto culture plates for identification, and observed specific morphological characteristics of the fungi.
- Six pure fungal cultures were preserved for future study, revealing distinct structural features of the pathogen, including the formation of ascomatal bases and aleurioconidia.
Attachment of bioinspired microfibrils in fluids: transition from a hydrodynamic to hydrostatic mechanism.
J R Soc Interface
April 2022
INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
Reversible and switchable adhesion of elastomeric microstructures has attracted significant interest in the development of grippers for object manipulation. Their applications, however, have often been limited to dry conditions and adhesion of such deformable microfibrils in the fluid environment is less understood. In the present study, we performed adhesion tests in silicone oil using single cylindrical microfibrils of a flat-punch shape with a radius of 80 µm.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!