scholarly journals Análisis de la solidificación de aleaciones ZN-AL a partir del método de Newton

2019 ◽  
pp. 1-7
Author(s):  
Sara Cruz-Guerrero ◽  
Israel Lazaro-Becerril ◽  
Jorge Eduardo Munguia-Huerta ◽  
Antonio Juanico-Loran ◽  
Hector Cruz-Mejia
Keyword(s):  
Stainless Steel ◽  
Primary Phase ◽  
Al Alloys ◽  
Cooling Curves ◽  
Lamellar Eutectic ◽  
Type K ◽  
Electronic File ◽  
Stainless Steel 304 ◽  
Eutectic Morphology ◽  
A Minor

The undercoolings of the primary and eutectic phases were determined in three Zn-Al alloys by the experimental cooling curves associated. The compositions of the alloys considered in this study were Zn-3%wAl, Zn-6%w Al and Zn-11% w Al in order to determinate the influence of the primary phase in the morphology obtained by the euetecic microsconstituent at the end of the solidification and its relationship with the underccoling registered in each step. The experimental cooling curves were obtained by a thermocouple type K inserted laterally at the center of a metallic mould of stainless steel 304, which dimentions were 4 cm of diameter and 7.5 cm of lengh. This thermocouple was connected to a data adqusiitior system and a computer in order to register these data in an electronic file. These data were processed following the algorithm of NTA method. The results obtained showed that a minor undercoolig is associated with a lamellar eutectic morphology.

Macro-Micro Modeling and Simulation of Solidification Kinetics of Pb-Sn Alloys

2006 ◽  
Vol 509 ◽  
pp. 171-176
Author(s):  
L. López ◽  
H. Cruz ◽  
B. Campillo ◽  
Carlos González-Rivera
Keyword(s):  
Heat Transfer ◽  
Solidification Rate ◽  
Primary Phase ◽  
Experimental Results ◽  
Eutectic Solidification ◽  
Cooling Curves ◽  
Solidification Kinetics ◽  
Eutectic Morphology ◽  
Micro Modeling ◽  
Kinetics Of

The purpose of this work is to explore the effect of the presence of two different primary phases on the microstructure and solidification kinetics of Pb-Sn alloys. The experimental results have been compared with predictions obtained from the Newton Thermal Analysis of cooling curves generated by a conventional heat transfer-solidification kinetics model. Three Pb-Sn alloys have been considered in this work in order to explore the solidification characteristics of the eutectic in hypoeutectic, hypereutectic and eutectic compositions. Experimental results indicate that the Pb-Sn eutectic morphology and the solidification rate depend on the nature of the pre-existent primary phase during eutectic solidification. From the observed discrepancies between experimental and simulated results it is concluded that further improvements are needed to simulate the solidification kinetics of eutectic microconstituents in the presence of pre-existing primary phases.

EXPLOSIVE CLADDING OF ALUMINIUM 5052-STAINLESS STEEL 304

2019 ◽  
Vol 14 (3) ◽  
Author(s):  
Saravanan S ◽  
Murugan G
Keyword(s):  
Stainless Steel ◽  
Interfacial Microstructure ◽  
Bend Angle ◽  
Flyer Plate ◽  
Layer Formation ◽  
Molten Layer ◽  
Explosive Cladding ◽  
Plate Velocity ◽  
Stainless Steel 304 ◽  
Loading Ratio

This study addresses the effect of process parameters viz., loading ratio (mass of explosive/mass of flyer plate) and preset angle on dynamic bend angle, collision velocity and flyer plate velocity in dissimilar explosive cladding. In addition, the variation in interfacial microstructure and mechanical strength of aluminium 5052-stainless steel 304 explosive clads is reported. The interface exhibits a characteristic undulating interface with a continuous molten layer formation. The interfacial amplitude increases with the loading ratio and preset angle. Maximum hardness is observed at regions closer to the interface

Evaluation of the residual stress in stainless steel 304L hydraulically expanded joints

2020 ◽  
pp. 095440892096401
Author(s):  
Ying Hong ◽  
Xuesheng Wang ◽  
Yan Wang ◽  
Zhao Zhang ◽  
Yong Han
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Yield Strength ◽  
Residual Stresses ◽  
Heat Exchangers ◽  
Nuclear Power ◽  
The Finite Element Method ◽  
Power Stations ◽  
Stainless Steel 304 ◽  
Initial Clearance

Stainless steel 304 L tubes are commonly used in the fabrication of heat exchangers for nuclear power stations. The stress corrosion cracking (SCC) of 304 L tubes in hydraulically expanded tube-to-tubesheet joints is the main reason for the failure of heat exchangers. In this study, 304 L hydraulically expanded joint specimens were prepared and the residual stresses of a tube were evaluated with both an experimental method and the finite element method (FEM). The residual stresses in the outer and inner surfaces of the tube were measured by strain gauges. The expanding and unloading processes of the tube-to-tubesheet joints were simulated by the FEM. Furthermore, an SCC test was carried out to verify the results of the experimental measurement and the FEM. There was good agreement between the FEM and the experimental results. The distribution of the residual stress of the tube in the expanded joint was revealed by the FEM. The effects of the expansion pressure, initial tube-to-hole clearance, and yield strength of the tube on the residual stress in the transition zone that lay between the expanded and unexpanded region of the tube were investigated. The results showed that the residual stress of the expanded joint reached the maximum value when the initial clearance was eliminated. The residual stress level decreased with the decrease of the initial tube-to-hole clearance and yield strength. Finally, an effective method that would reduce the residual stress without losing tightness was proposed.

scholarly journals Radiological Evaluation of Stainless Steel Crowns Placed on Permanent Teeth in Patients Treated under General Anaesthesia

2021 ◽  
Vol 18 (5) ◽  
pp. 2509
Author(s):  
Marie-Laure Munoz-Sanchez ◽  
Natacha Linas ◽  
Nicolas Decerle ◽  
Valérie Collado ◽  
Denise Faulks ◽  
...  
Keyword(s):  
Stainless Steel ◽  
General Anaesthesia ◽  
Alveolar Bone ◽  
Dental Treatment ◽  
Glass Ionomer Cement ◽  
Permanent Teeth ◽  
Marginal Adaptation ◽  
Permanent Molars ◽  
A Minor ◽  
Ionomer Cement

Evidence-based evaluations of dental treatment are needed to support the development of special care dentistry services. This retrospective study was designed to collect and analyse X-ray images of permanent teeth restored with stainless steel crowns (SSC) in patients treated under general anaesthesia. Between 2013 and 2019, 360 permanent molars were crowned with SSCs in 198 adult patients. One calibrated investigator used an original validated tool to evaluate four radiographic criteria for molars restored with SSCs: i) marginal adaptation; ii) interdental proximal contact; iii) the presence of glass ionomer cement overflow; and iv) the loss of alveolar bone. Overall, no defect or a minor defect was reported for the majority of SSCs for the criteria “Marginal adaptation” (62.5%, n = 320), “Proximal contact” (82.2%, n = 236) and “Cement overflow” (95.8%, n = 337). Alveolar bone resorption was reported in 8.3% of cases, n = 14, after a mean period of 8.9 ± 14.3 months. It was shown that the restoration of permanent teeth using SSCs placed under general anaesthesia presents a low risk of periodontal morbidity in the medium term when assessed radiographically.

A Noncyclic Method for Determination of Accumulated Strain in Stainless Steel 304 Pressure Vessels

2014 ◽  
Vol 136 (6) ◽  
Author(s):  
Gongfeng Jiang ◽  
Gang Chen ◽  
Liang Sun ◽  
Yiliang Zhang ◽  
Xiaoliang Jia ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Internal Pressure ◽  
Pressure Vessel ◽  
Peak Stress ◽  
Pressure Vessels ◽  
Experimental Results ◽  
Elastic Domain ◽  
Ratcheting Strain ◽  
Stainless Steel 304 ◽  
Accumulated Strain

Experimental results of uniaxial ratcheting tests for stainless steel 304 (SS304) under stress-controlled condition at room temperature showed that the elastic domain defined in this paper expands with accumulation of plastic strain. Both ratcheting strain and viscoplastic strain rates reduce with the increase of elastic domain, and the total strain will be saturated finally. If the saturated strain and corresponded peak stress of different experimental results under the stress ratio R ≥ 0 are plotted, a curve demonstrating the material shakedown states of SS304 can be constituted. Using this curve, the accumulated strain in a pressure vessel subjected to cyclic internal pressure can be determined by only an elastic-plastic analysis, and without the cycle-by-cycle analysis. Meanwhile, a physical experiment of a thin-walled pressure vessel subjected to cyclic internal pressure has been carried out to verify the feasibility and effectiveness of this noncyclic method. By comparison, the accumulated strains evaluated by the noncyclic method agreed well with those obtained from the experiments. The noncyclic method is simpler and more practical than the cycle-by-cycle method for engineering design.

Sign in / Sign up

Export Citation Format

Share Document