2篇
您的检索式：作者名="Andrew M.Mullis"
|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Microstructural development and mechanical properties of drop tube atomized Al-2.85 wt%Fe显示文摘Al-2.85 wt%Fe alloy has been subjected to non-equilibrium container-less solidification using a 6.5 m drop tube.Spherical samples were collected and sieved into 7 sizes fractions ranging from 850μm to 53μm,with the estimated cooling rates being 150 to 11000 K s^(-1)respectively.XRD analysis was employed on all droplet size fractions for identification and evolution of the phases,showing that Al,Al_(6)Fe and Al_(13)Fe_(4)were formed for all sizes while Al_(5)Fe_(2)was observed only in droplets≤150μm in diameter.Microstructural evaluation was conducted by using SEM and optical microscopy,showing that droplet larger than 300μm in diameter exhibited distinct morphologies;microcellular,dendriticα-Al with inter-dendritic Al_(13)Fe_(4)eutectic and an AI-Al_(6)Fe eutectic region.With increasing cooling rate,the Al-Al_(6)Fe region disappears.EDX analysis reveals that increasing the cooling rate increased the dissolved Fe content inα-Al from 0.37 wt%Fe to 1.105 wt%Fe,and correspondingly the eutectic fraction decreased from 49.7 vol.%to 26.7 vol.%.Measurement of the lamellar spacing allowed the eutectic growth velocity and interfacial undercooling to be calculated,wherein the Al-rich boundary of the eutectic coupled zone could be reconstructed.This shows a coupled zone skewed significantly towards the intermetallic side of the eutectic.In order to understand the effect of non-equilibrium the solidification on the mechanical properties micro hardness of the droplets was measured.The micro-hardness has risen from 55.3 HV_(0.01)to 66.5 HV_(0.01)for≥850μm and≤75μm droplets,respectively. | Mehmet R.Abul Robert F.Cochrane Andrew M.Mullis | 2022 | Journal of Materials Science & Technology2022，，9： | 0 |
| 2 | On the Fully Implicit Solution of a Phase-Field Model for Binary Alloy Solidification in Three Dimensions显示文摘A fully implicit numerical method,based upon a combination of adaptively refined hierarchical meshes and geometric multigrid,is presented for the simulation of binary alloy solidification in three space dimensions.The computational techniques are presented for a particular mathematical model,based upon the phase-field approach,however their applicability is of greater generality than for the specific phase-field model used here.In particular,an implicit second order time discretization is combined with the use of second order spatial differences to yield a large nonlinear system of algebraic equations as each time step.It is demonstrated that these equations may be solved reliably and efficiently through the use of a nonlinear multigrid scheme for locally refined grids.In effect this paper presents an extension of earlier research in two space dimensions(J.Comput.Phys.,225(2007),pp.1271–1287)to fully three-dimensional problems.This extension is validated against earlier two-dimensional results and against some of the limited results available in three dimensions,obtained using an explicit scheme.The efficiency of the implicit approach and the multigrid solver are then demonstrated and some sample computational results for the simulation of the growth of dendrite structures are presented. | Christopher E.Goodyer Peter K.Jimack Andrew M.Mullis Hongbiao Dong Yu Xie | 2012 | Advances in Applied Mathematics and Mechanics2012，4，6： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员