Journal of Light Metals最新文献_第4页

Modelling of light metals: From the atomic scale to the processing of automotive and aerospace components 轻金属的建模:从原子尺度到汽车和航空部件的加工

Journal of Light Metals Pub Date : 2002-08-01 DOI: 10.1016/S1471-5317(03)00003-8

P. Lee

引用次数: 0

Isothermal subtransus forging of Ti–6Al–2Sn–4Zr–6Mo Ti-6Al-2Sn-4Zr-6Mo等温亚横锻

Journal of Light Metals Pub Date : 2002-08-01 DOI: 10.1016/S1471-5317(02)00044-5

M. Jackson, R. Dashwood, L. Christodoulou, H. Flower

引用次数: 13

Prediction of internal cracking in a direct-chill cast, high strength, Al–Mg–Si alloy 直接冷铸高强度Al–Mg–Si合金内部裂纹的预测

Journal of Light Metals Pub Date : 2002-08-01 DOI: 10.1016/S1471-5317(02)00042-1

Hiromi Nagaumi , Takateru Umeda

{"title":"Prediction of internal cracking in a direct-chill cast, high strength, Al–Mg–Si alloy","authors":"Hiromi Nagaumi , Takateru Umeda","doi":"10.1016/S1471-5317(02)00042-1","DOIUrl":"https://doi.org/10.1016/S1471-5317(02)00042-1","url":null,"abstract":"<div><p>In order to develop a new method for predicting the internal cracking in direct-chill (DC) cast billets, tensile tests of the mushy zone of high-strength Al–Mg–Si alloys were undertaken, and solidification and thermal stress simulations of the DC casting process were performed. In this study, the solidification process was calculated using a commercial solidification package, CAPFLOW and the thermal stress was analysed with a structural analysis package, ANSYS. The thermal histories from CAPFLOW were used as input data to an elasto-plasticity model which simulated the thermal stress and deformation of the billet during the casting process. Prediction of the internal cracking in the DC billet was carried out by comparing the equivalent plastic strain obtained from the elasto-plasticity thermal deformation analysis with the fracture strain of the alloy obtained by high-temperature tensile tests. The analysis results in the mushy zone show that the equivalent plastic strain is an important factor in the occurrence of internal cracking: when the equivalent plastic strain exceeds the fracture strain of the alloy, the billet will crack, and the predictions obtained by this method are in good agreement with the experimental results.</p></div>","PeriodicalId":100798,"journal":{"name":"Journal of Light Metals","volume":"2 3","pages":"Pages 161-167"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1471-5317(02)00042-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72106993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 25

Modelling issues in macrosegregation predictions in direct chill castings 直接激冷铸件宏观偏析预测中的建模问题

Journal of Light Metals Pub Date : 2002-08-01 DOI: 10.1016/S1471-5317(02)00041-X

B.C.H Venneker , L Katgerman

{"title":"Modelling issues in macrosegregation predictions in direct chill castings","authors":"B.C.H Venneker , L Katgerman","doi":"10.1016/S1471-5317(02)00041-X","DOIUrl":"https://doi.org/10.1016/S1471-5317(02)00041-X","url":null,"abstract":"<div><p>Macrosegregation is a major concern in direct chill (DC) casting because it can lead to non-uniform mechanical properties which affects the behaviour of the metal during downstream forming and heat treatments. The main mechanism behind macrosegregation is well understood: the transport of segregated alloying elements at the scale of the casting by the relative movement of liquid and solid phase in the mushy zone. While previous numerical simulations of DC-casting investigated the effects of one or more of the mechanisms leading to macrosegregation, one modelling issue is relatively unexplored, i.e. the effect of discretisation errors, i.e. numerical diffusion and dispersion, on the predictions. This paper addresses the performance of several discretisation schemes in five typical fluid flow benchmarks which all have some similarities with the flow in the liquid sump of a DC-cast ingot. A selection of the studied discretisation schemes is then used to simulate macrosegregation in an Al–4.5wt.%Cu alloy in two particular cases: a small diameter ingot with thermal buoyancy only, and a large diameter ingot in which both thermosolutal buoyancy and solidification shrinkage is taken into account. Overall best scheme was found to be the STOIC scheme, both for the momentum equations as well as for the species transport equation. Simulations with the small diameter ingot showed that false segregation caused by numerical diffusion is found with the poorly performing schemes. In the case of the large diameter ingot the choice of the discretisation scheme has shown to affect the sign of centreline segregation. Predictions with the STOIC scheme are qualitatively in agreement with experimental data.</p></div>","PeriodicalId":100798,"journal":{"name":"Journal of Light Metals","volume":"2 3","pages":"Pages 149-159"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1471-5317(02)00041-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72106994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 40

Modelling issues in macrosegregation predictions in direct chill castings 直接冷铸宏观偏析预测中的建模问题

Journal of Light Metals Pub Date : 2002-08-01 DOI: 10.1016/S1471-5317(02)00041-X

B.C.H. Venneker, L. Katgerman

引用次数: 40

A review of microstructural computer models used to simulate grain growth and recrystallisation in aluminium alloys 用于模拟铝合金晶粒生长和再结晶的微观结构计算机模型综述

Journal of Light Metals Pub Date : 2002-08-01 DOI: 10.1016/S1471-5317(02)00039-1

Mark A. Miodownik

引用次数: 127

Three-dimensional smoothed particle hydrodynamics simulation of high pressure die casting of light metal components 轻金属零件高压压铸三维光滑颗粒流体力学模拟

Journal of Light Metals Pub Date : 2002-08-01 DOI: 10.1016/S1471-5317(02)00043-3

P. Cleary, J. Ha

引用次数: 24

Optimization of the Ti–0.2Pd alloy properties through heat treatments 热处理对Ti–0.2Pd合金性能的优化

Journal of Light Metals Pub Date : 2002-05-01 DOI: 10.1016/S1471-5317(02)00023-8

J.A Picas, A Forn, F.J Gil

引用次数: 7

Optimization of the Ti–0.2Pd alloy properties through heat treatments 通过热处理优化Ti-0.2Pd合金性能

Journal of Light Metals Pub Date : 2002-05-01 DOI: 10.1016/S1471-5317(02)00023-8

J. A. Picas, A. Forn, F. Gil

引用次数: 7

A quench sensitivity study on the novel Al–Li–Cu–X alloy AF/C 458 新型Al–Li–Cu–X合金AF/C 458的淬火敏感性研究

Journal of Light Metals Pub Date : 2002-05-01 DOI: 10.1016/S1471-5317(02)00024-X

B.M Gable, A.A Csontos, E.A Starke Jr.

{"title":"A quench sensitivity study on the novel Al–Li–Cu–X alloy AF/C 458","authors":"B.M Gable, A.A Csontos, E.A Starke Jr.","doi":"10.1016/S1471-5317(02)00024-X","DOIUrl":"https://doi.org/10.1016/S1471-5317(02)00024-X","url":null,"abstract":"<div><p><span>The quench sensitivity of a novel Al–Li–Cu–X alloy, designated AF/C 458, was investigated through employing cooling rates of 1.8, 68 and 290 °C/s from the solution heat treatment temperature. Two versions of this alloy were investigated; an unrecrystallized temper consisting of equiaxed subgrains approximately 10 μm in diameter, with the second having recrystallized grains, absent of substructure. Subsequent mechanical testing, fractography and microstructural characterization were used in order to investigate the degree of quench sensitivity for naturally and artificially aged specimens. Varying levels of pre-age </span>plastic deformation were also implemented for the artificially aged specimens.</p><p>The slowest quench rate from the solution heat treatment correlated with the highest strength in the as-quenched condition but with subsequent minimal gains from natural aging. The as-quenched strength is attributed to the precipitation of large Al<sub>2</sub>CuLi(T<sub>1</sub>) plates during cooling. Conversely, the rapidly quenched specimens were free of coarse precipitation and exhibited superior gains during natural aging at ambient temperature due to the enhanced nucleation and growth of Al<sub>3</sub>Li(δ<sup>′</sup>). Despite the presence of the coarse T<sub>1</sub> precipitation in the slowly cooled specimens, the strength did not vary by more than 10% between the three quench rates for a given heat treatment. However, there was a consistent trend of enhanced ductility with increasing quench rate from the solution heat treatment temperature for each aged condition. Samples with the recrystallized grain structure had lower strengths in the as-quenched and naturally aged conditions when compared to samples with an unrecrystallized grain structure. Different levels of pre-age deformation did not affect the quench sensitivity for the under-aged conditions investigated in this study.</p></div>","PeriodicalId":100798,"journal":{"name":"Journal of Light Metals","volume":"2 2","pages":"Pages 65-75"},"PeriodicalIF":0.0,"publicationDate":"2002-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1471-5317(02)00024-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72115467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 27