Advanced manufacturing processes such as additive manufacturing offer now the capability to control material placement at unprecedented length scales and thereby dramatically open up the design space.This includes the...Advanced manufacturing processes such as additive manufacturing offer now the capability to control material placement at unprecedented length scales and thereby dramatically open up the design space.This includes the considerations of new component topologies as well as the architecture of material within a topology offering new paths to creating lighter and more efficient structures.Topology optimization is an ideal tool for navigating this multiscale design problem and leveraging the capabilities of advanced manufacturing technologies.However,the resulting design problem is computationally challenging as very fine discretizations are needed to capture all micro-structural details.In this paper,a method based on reduction techniques is proposed to perform efficiently topology optimization at multiple scales.This method solves the design problem without length scale separation,i.e.,without iterating between the two scales.Ergo,connectivity between space-varying micro-structures is naturally ensured.Several design problems for various types of micro-structural periodicity are performed to illustrate the method,including applications to infill patterns in additive manufacturing.展开更多
Laser additive manufacturing(LAM) of tungsten carbide metal matrix composites(MMCs) has been evaluated for surface modification of hot die forming tools,cutting edges,glass tooling,extrusion mandrels,and other abrasiv...Laser additive manufacturing(LAM) of tungsten carbide metal matrix composites(MMCs) has been evaluated for surface modification of hot die forming tools,cutting edges,glass tooling,extrusion mandrels,and other abrasive wear applications.This work focuses on transitions from tool steels to MMCs through a single pass laser powder deposition operation.Issues related to the application of various metal powders and carbides used include surface hardness,porosity,cracking,and dilution.These issues along with factory results that were obtained during this project are discussed.展开更多
基金This research was supported in part by the US National Science Foundation(NSF)under Grant Number 1462453in part by the National Aeronautics and Space Administration(NASA)under Grant Number 80NSSC18K0428.Any opinions,findings,and conclusions or recommendations expressed in this article are those of the author(s)and do not necessarily reflect the views of NSF or NASA.
文摘Advanced manufacturing processes such as additive manufacturing offer now the capability to control material placement at unprecedented length scales and thereby dramatically open up the design space.This includes the considerations of new component topologies as well as the architecture of material within a topology offering new paths to creating lighter and more efficient structures.Topology optimization is an ideal tool for navigating this multiscale design problem and leveraging the capabilities of advanced manufacturing technologies.However,the resulting design problem is computationally challenging as very fine discretizations are needed to capture all micro-structural details.In this paper,a method based on reduction techniques is proposed to perform efficiently topology optimization at multiple scales.This method solves the design problem without length scale separation,i.e.,without iterating between the two scales.Ergo,connectivity between space-varying micro-structures is naturally ensured.Several design problems for various types of micro-structural periodicity are performed to illustrate the method,including applications to infill patterns in additive manufacturing.
基金Supported by the U.S. Department of Energy(DOE),Office of Industrial Technology under contract DE-PS0703ID14425:Industrial Materials for the Future Program and through contracts with Spirex Corporation and Owens-Illinois
文摘Laser additive manufacturing(LAM) of tungsten carbide metal matrix composites(MMCs) has been evaluated for surface modification of hot die forming tools,cutting edges,glass tooling,extrusion mandrels,and other abrasive wear applications.This work focuses on transitions from tool steels to MMCs through a single pass laser powder deposition operation.Issues related to the application of various metal powders and carbides used include surface hardness,porosity,cracking,and dilution.These issues along with factory results that were obtained during this project are discussed.