Recent Submissions

  • Thermal Properties of Powders 

    Xue, Samuel; Barlow, J.W. (1990)
    This paper presents measurements of the specific heats of various powders, including nylon, ABS, PVC, and two kinds of wax. An unsteady-state conduction technique is also presented for measuring the thermal conductivities ...
  • Solid Modeling and Stereolithography as a Solid Freeform Fabrication Technique at Texas Instruments Incorporated 

    Baumgardner, Owen; Blake, Paul (1990)
    Over the past 25 years, the CAE/CAD/CAM industry has developed technological advances that have provided industrial users the ability to increase productivity and decrease the cycle time necessary for product development. ...
  • Sintering Rates in the Selective Laser Sintering Process 

    Nelson, Christian; Barlow, J.W. (1990)
    This paper presents. a procedure to determine rates of sintering as a function of temperature using an isothermaloven. The rate of height change of a powder sample in the oven at temperatures near the Tg or Tm is measured. ...
  • A Computer Model for Laser Photopolymerization 

    Flach, Lawrance; Chartoff, Richard P. (1990)
    A computer model for a laser induced photopolymerization process has been established which simulates stereolithography. The model couples irradiation, chemical reaction, and heat transfer equations to provide insights ...
  • Parametric Analysis of the Selective Laser Sintering Process 

    Martin Sun, Ming-shen; Beaman, Joseph J.; Barlow, Joel W. (1990)
    Qualitative and quantitative analyses are required to develop Selective Laser Sintering into a viable Manufacturing process. A simplified mathematical model for sintering incorporating the heat tJ;ansfer equation. and ...
  • Geometric Modeling for Rapid Prototyping and Tool Fabrication 

    Gursoz, E. Levent; Weiss, Lee E.; Prinz, Fritz B. (1990)
    This paper describes the application of a non-manifold geometric modeling environment, NOODLES, to a Rapid Tool Fabrication System. This system integrates stereolithography and thermal spray deposition into a CAD/CAM ...
  • Contour Following for Scanning Control in SFF Application : Control Trajectory Planning 

    Wu, Ying-Jeng Engin; Beaman, J.J. (1990)
    Geometric contour following for scanning control in SFF application is used to refine the boundary ofthe parts for increasing the accuracy or to develop the capability to arrange various scanning directions and paths for ...
  • A New CAD Model Format For SFF Machines? 

    Darrah, James; Wielgus, Martin (1990)
    This paper addresses the issue of a standard input data fonnat for Solid Freefonn Fabrication (SFF) machines. Currently implemented approaches do not address the different aspects of Solid Freefonn Fabrication. This paper ...
  • ALPHA_I, Remote Manufacturing, and Solid Freeform Fabrication 

    Drake, Samuel H. (1990)
    Alpha_l is a nonuniform rational B-spline (NURBs) based solid modeling system that has been developed at the University of Utah over the past 10 years. In addition to being useful in modeling objects that are described ...
  • Steel-Based Sprayed Metal Tooling 

    Fussell, P.S.; Weiss, L.E. (1990)
    A strategy for building sprayed steel tooling by arc spray deposition is discussed in this paper. Depositing steel is crucial for moving sprayed metal toolingfrom prototype applications to superior prototype and ...
  • Selective Laser Sintering of Binary Metallic Powder 

    Manriquez-Frayre, J.A.; Bourell, D.L. (1990)
    A selective laser sintering technique has been used to process metal powders and powder blends. Precursor powders include copper, tin, a 70Pb-30Sn solder and their blends. Excessive balling due to surface free energy ...
  • Prediction of the Thermal Conductivity of Beds Which Contain Polymer Coated Metal Particles 

    Badrinarayan, B.; Barlow, J.W. (1990)
    Structural parts of ceramics or metals can, in principle, be made by laser sintering polymer coated ceramic or metal powders, followed by conventional methods for removing the binder and sintering in ovens. Understanding ...
  • Solid Freeform Fabrication by Selective Area Laser Deposition 

    Zong, G.S.; Carnes, R.; Wheat, H.G.; Marcus, H.L. (1990)
    Laser chemical vapor deposition is capable of selective area deposition of thin fums at high spatial resolution, and in the present work this advantage was used to perform solid freeform fabrication (SFF). The pyrolytic ...
  • Modeling of Selective Area Laser Deposition for Solid Freeform fabrication 

    Jacquot, Y.; Zong, S.; Marcus, H.L. (1990)
    The results of a theoretical study of the selective area laser deposition process used for Solid Freeform Fabrication (SFF) from gas phase is presented. We show how the deposition profile of carbon deposited via pyrolytic ...
  • Deisign of a SoliidFreefotm· Fabrication Diamond Reactor 

    Thissell, W.Richards; Tompkins, James; Marcus, Harris L. (1990)
    Solid Freeform Fabrication (SFF) has progressed from the visualization aided stage of computer aided designs (CAD) to rapid prototyping of structural parts. Among the promising techniques for producing structural prototypes ...
  • Three Dimensional Printing: Rapid Tooling and Prototypes Directly from CAD Representation 

    Sachs, Emanuel; Cima, Michael; Cornie, James (1990)
    Industrial productivity and competitive success depend on fast, efficient product development technologies. The flexible manufacture of tooling and mechanical prototypes can greatly reduce the time required for bringing ...
  • Selective Laser Sintering of Ceramic Materials 

    Lakshminarayan, Uday; Ogrydiziak, Stan; Marcus, H.L. (1990)
    This paper will focus on efforts to develop the alumina - ammonium phosphate material system for Solid Freeform Fabrication. When the powder mix is irradiated with a laser beam, ammonium phosphate ( m.p. """ 190 0 C ) ...
  • Microencapsulation of Finely Divided Ceramic Powders 

    Vail, N.K.; Barlow, J.W. (1990)
    Polymer coated alumina particles have been prepared by spray drying alumina powder with a polymer emulsion. Powders containing a maximum of 50% wt. were obtained. The coated particles were compared to mixtures of alumina ...
  • Solid Freeform Fabrication An Advanced Manufacturing Approach 

    Bourell, D.L.; Beaman, J.J.; Marcus, H.L.; Barlow, J.W. (1990)
  • 1990 Annual International Solid Freeform Fabrication Symposium Table of Contents 

    Laboratory for Freeform Fabrication; University of Texas at Austin (1990)