The effectiveness of combining rolling deformation with Wire–Arc Additive Manufacture on β-grain refinement and texture modification in Ti–6Al–4V

Abstract In Additive Manufacture (AM), with the widely used titanium alloy Ti–6Al–4V, the solidification conditions typically result in undesirable, coarse-columnar, primary β grain structures. This can result in a strong texture and mechanical anisotropy in AM components. Here, we have investigated the efficacy of a new approach to promote β grain refinement in Wire–Arc Additive Manufacture (WAAM) of large scale parts, which combines a rolling step sequentially with layer deposition. It has been found that when applied in-process, to each added layer, only a surprisingly low level of deformation is required to greatly reduce the β grain size. From EBSD analysis of the rolling strain distribution in each layer and reconstruction of the prior β grain structure, it has been demonstrated that the normally coarse centimetre scale columnar β grain structure could be refined down to

[1]  T. K. Kundra,et al.  Additive Manufacturing Technologies , 2018 .

[2]  C. Colin,et al.  As-Fabricated and Heat-Treated Microstructures of the Ti-6Al-4V Alloy Processed by Selective Laser Melting , 2011 .

[3]  Weilie Zhou,et al.  Scanning Microscopy for Nanotechnology: Techniques and Applications , 2007 .

[4]  Integration of Deformation Processing with Additive Manufacture of Ti-6Al-4V Components for Improved β Grain Structure and Texture , 2015 .

[5]  B. Stucker,et al.  Microstructures and Mechanical Properties of Ti6Al4V Parts Fabricated by Selective Laser Melting and Electron Beam Melting , 2013, Journal of Materials Engineering and Performance.

[6]  Paul A. Colegrove,et al.  Microstructure and residual stress improvement in wire and arc additively manufactured parts through high-pressure rolling , 2013 .

[7]  P. Colegrove,et al.  Microstructure and Mechanical Properties of Wire and Arc Additive Manufactured Ti-6Al-4V , 2013, Metallurgical and Materials Transactions A.

[8]  Matthew S. Dargusch,et al.  Grain-refinement mechanisms in titanium alloys , 2008 .

[9]  J S Tiley,et al.  Additive Manufacturing of Aerospace Alloys for Aircraft Structures , 2006 .

[10]  David W. Rosen,et al.  Additive Manufacturing Technologies: Rapid Prototyping to Direct Digital Manufacturing , 2009 .

[11]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[12]  P. Prangnell,et al.  Effect of Wall Thickness Transitions on Texture and Grain Structure in Additive Layer Manufacture (ALM) of Ti-6Al-4V , 2012 .

[13]  J. E. Sorauf,et al.  Origin of microstructural diversity , 2010 .

[14]  Jun-Yun Kang,et al.  Phase Analysis on Dual-Phase Steel Using Band Slope of Electron Backscatter Diffraction Pattern , 2013, Microscopy and Microanalysis.

[15]  S. L. Semiatin,et al.  Microstructure and texture evolution during solidification processing of Ti–6Al–4V , 2003 .

[16]  P. Colegrove,et al.  Microstructure of Interpass Rolled Wire + Arc Additive Manufacturing Ti-6Al-4V Components , 2015, Metallurgical and Materials Transactions A.

[17]  N. Gey,et al.  Specific analysis of EBSD data to study the texture inheritance due to the β → α phase transformation , 2003 .

[18]  W. G. Burgers,et al.  The habit plane of the zirconium transformation , 1952 .

[19]  Matthew Thomas,et al.  Development of Microstructure and Crystallographic Texture during Stationary Shoulder Friction Stir Welding of Ti-6Al-4V , 2011 .

[20]  P. Prangnell,et al.  In‐Situ High Temperature EBSD Analysis of the Effect of a Deformation Step on the Alpha to Beta Transition in Additive Manufactured Ti‐6Al‐4V , 2016 .

[21]  Berthold Scholtes,et al.  On the influence of mechanical surface treatments—deep rolling and laser shock peening—on the fatigue behavior of Ti–6Al–4V at ambient and elevated temperatures , 2003 .

[22]  M. Bermingham,et al.  Effects of boron on microstructure in cast titanium alloys , 2008 .

[23]  Jing Liang,et al.  Microstructures of laser-deposited Ti–6Al–4V , 2004 .

[24]  P. Davies.  An investigation of microstructure and texture evolution in the Near-α titanium alloy timetal 834 , 2009 .

[25]  Yunheng Ji.  MORPHOLOGY , 1937, A Grammar of Italian Sign Language (LIS).

[26]  J. Mei,et al.  Microstructure study of direct laser fabricated Ti alloys using powder and wire , 2006 .

[27]  Christoph Leyens,et al.  Morphology, microstructure, and hardness of titanium (Ti-6Al-4V) blocks deposited by wire-feed additive layer manufacturing (ALM) , 2012 .

[28]  W. M. Rainforth,et al.  The Impact of Strain Reversal on Microstructure Evolution and Orientation Relationships in Ti-6Al-4V with an Initial Alpha Colony Microstructure , 2014, Metallurgical and Materials Transactions A.

[29]  I. L. Dillamore,et al.  PREFERRED ORIENTATION IN WROUGHT AND ANNEALED METALS , 1965 .

[30]  Bernd Baufeld,et al.  Mechanical properties of Ti-6Al-4V specimens produced by shaped metal deposition , 2009, Science and technology of advanced materials.

[31]  M. Preuss,et al.  Effect of β grain growth on variant selection and texture memory effect during α → β → α phase transformation in Ti-6 Al-4 v , 2012 .

[32]  N. Gey,et al.  The calculation of a parent grain orientation from inherited variants for approximate (b.c.c.–h.c.p.) orientation relations , 2002 .

[33]  T. C. Lindley,et al.  The role of microtexture on the faceted fracture morphology in Ti–6Al–4V subjected to high-cycle fatigue , 2010 .

[34]  J. M. Vitek,et al.  Correlation between solidification parameters and weld microstructures , 1989 .

[35]  Thomas Edward Buchheit,et al.  Investigating the limits of polycrystal plasticity modeling , 2003 .

[36]  Stewart Williams,et al.  Morphology investigation on direct current pulsed gas tungsten arc welded additive layer manufactured Ti6Al4V alloy , 2011 .

[37]  H. Wenk,et al.  In situ observation of texture evolution during α → β and β → α phase transformations in titanium alloys investigated by neutron diffraction , 2007 .

[38]  Zhengxiao Guo,et al.  Microstructural evolution of a Ti–6Al–4V alloy during β-phase processing: experimental and simulative investigations , 2004 .

[39]  Paul A. Colegrove,et al.  Investigation of the benefits of plasma deposition for the additive layer manufacture of Ti–6Al–4V , 2012 .

[40]  Paul A. Colegrove,et al.  Improved microstructure and increased mechanical properties of additive manufacture produced TI-6AL-4V by interpass cold rolling , 2013 .

[41]  J. Mei,et al.  Microstructure and properties of a laser fabricated burn-resistant Ti alloy , 2004 .

[42]  Ming-Chuan Leu,et al.  Progress in Additive Manufacturing and Rapid Prototyping , 1998 .

[43]  Z. M. Wang,et al.  Titanium alloys and their machinability—a review , 1997 .

[44]  Todd Palmer,et al.  Anisotropic tensile behavior of Ti-6Al-4V components fabricated with directed energy deposition additive manufacturing , 2015 .

[45]  U. F. Kocks,et al.  Texture and Anisotropy: Preferred Orientations in Polycrystals and their Effect on Materials Properties , 1998 .

[46]  A. Antonysamy,et al.  Microstructure, texture and mechanical property evolution during additive manufacturing of Ti6Al4V alloy for aerospace applications , 2012 .

[47]  A. A. Salem,et al.  Variant Selection During Cooling after Beta Annealing of Ti-6Al-4V Ingot Material , 2012, Metallurgical and Materials Transactions A.

[48]  S. Kelly,et al.  Microstructural evolution in laser-deposited multilayer Ti-6Al-4V builds: Part II. Thermal modeling , 2004 .

[49]  S. S. Al-Bermani,et al.  The Origin of Microstructural Diversity, Texture, and Mechanical Properties in Electron Beam Melted Ti-6Al-4V , 2010 .