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AISI/DOE Technology Roadmap Program: Improved Surface Quality of Exposed Automotive Sheet Steels

Description: Surface quality of sheet steels is an important economic and technical issue for applications such as critical automotive surfaces. This project was therefore initiated to develop a more quantitative methodology for measuring surface imperfections, and to assess their response to forming and painting, particularly with respect to their visibility or invisibility after painting. The objectives were met, and included evaluation of a variety of imperfections present on commercial sheet surfaces or simulated using methods developed in the laboratory. The results are expected to have significant implications with respect to the methodology for assessing surface imperfections, development of quantitative criteria for surface inspection, and understanding and improving key painting process characteristics that influence the perceived quality of sheet steel surfaces.
Date: October 10, 2002
Creator: Speer, John G.; Matlock, David K.; Meyers, Noel & Choi, Young-Min
Partner: UNT Libraries Government Documents Department

Mask substrate requirements and development for extreme ultraviolet lithography (EUVL)

Description: The mask is deemed one of the areas that require significant research and development in EUVL. Silicon wafers will be used for mask substrates for an alpha-class EUVL exposure tool due to their low-defect levels and high quality surface finish. However, silicon has a large coefficient of thermal expansion that leads to unacceptable image distortion due to absorption of EUV light. A low thermal expansion glass or glass-ceramic is likely to be required in order to meet error budgets for the 70nm node and beyond. Since EUVL masks are used in reflection, they are coated with multilayers prior to patterning. Surface imperfections, such as polishing marks, particles, scratches, or digs, are potential nucleation sites for defects in the multilayer coating, which could result in the printed defects. Therefore we are accelerating developments in the defect reduction and surface finishing of low thermal expansion mask substrates in order to understand long-term issues in controlling printable defects, and to establish the infrastructure for supplying masks. In this paper, we explain the technical requirements for EUVL mask substrates and describe our efforts in establishing a SEMI standard for EUVL masks. We will also report on the early progress of our suppliers in producing low thermal-expansion mask substrates for our development activities.
Date: September 28, 1999
Creator: Hector, S D; Shell, M; Taylor, J S & Tong, W M
Partner: UNT Libraries Government Documents Department

Numerical analysis of the ultraprecision machining of copper

Description: Modeling of the ultraprecision machining process can aid in the understanding of the relative importance of various process parameters and ultimately lead to improved methods of generating ultraprecision surfaces such as those required for metal optics and single crystal microelectronics substrates. Any modeling method should be verified by direct comparison to experimental data. Until recently it has been difficult to accurately measure the cutting edge, or sharpness, of a diamond tool; and therefore, most models have assumed an infinitely sharp cutting tip. With the relatively new technology of the Atomic Force Microscope (AFM), the cutting edge of single crystal diamond tools can be quantitatively described. Ultraprecision machining experiments using an AFM characterized cutting tool and orthogonal geometry have been performed. These experiments have resulted in measured cutting and thrust forces for different depths of cut in copper (Te-Cu: 99.4-99.5% Cu, 0.5-0.6% Te, 4-5 micron grain size, 225 MPa yield strength) with a well characterized diamond tool. By using this actual tool tip geometry the authors have been able to develop a model that can predict cutting and thrust forces for depths of cut on the order of the sharpness of the tool. Forces predicted by this numerical model are compared to the experimentally measured forces.
Date: March 1, 1995
Creator: Stevens, R.; Anderson, C.; Rhorer, R. & Lucca, D.
Partner: UNT Libraries Government Documents Department

Development and testing of an active boring bar for increased chatter immunity

Description: Recent advances in smart materials have renewed interest in the development of improved manufacturing processes featuring sensing, processing, and active control. In particular, vibration suppression in metal cutting has received much attention because of its potential for enhancing part quality while reducing the time and cost of production. Although active tool clamps have been recently demonstrated, they are often accompanied by interfacing issues that limit their applicability to specific machines. Under the auspices of the Laboratory Directed Research and Development program, the project titled {open_quotes}Smart Cutting Tools for Precision Manufacturing{close_quotes} developed an alternative approach to active vibration control in machining. Using the boring process as a vehicle for exploration, a commercially available tool was modified to incorporate PZT stack actuators for active suppression of its bending modes. Since the modified tool requires no specialized mounting hardware, it can be readily mounted on many machines. Cutting tests conducted on a horizontal lathe fitted with a hardened steel workpiece verify that the actively damped boring bar yields significant vibration reduction and improved surface finishes as compared to an unmodified tool.
Date: December 1, 1997
Creator: Redmond, J. & Barney, P.
Partner: UNT Libraries Government Documents Department

Automatic tool path generation for finish machining

Description: A system for automatic tool path generation was developed at Sandia National Laboratories for finish machining operations. The system consists of a commercially available 5-axis milling machine controlled by Sandia developed software. This system was used to remove overspray on cast turbine blades. A laser-based, structured-light sensor, mounted on a tool holder, is used to collect 3D data points around the surface of the turbine blade. Using the digitized model of the blade, a tool path is generated which will drive a 0.375 inch diameter CBN grinding pin around the tip of the blade. A fuzzified digital filter was developed to properly eliminate false sensor readings caused by burrs, holes and overspray. The digital filter was found to successfully generate the correct tool path for a blade with intentionally scanned holes and defects. The fuzzified filter improved the computation efficiency by a factor of 25. For application to general parts, an adaptive scanning algorithm was developed and presented with simulation results. A right pyramid and an ellipsoid were scanned successfully with the adaptive algorithm.
Date: March 1, 1997
Creator: Kwok, Kwan S.; Loucks, C.S. & Driessen, B.J.
Partner: UNT Libraries Government Documents Department

The fabrication of millimeter-wavelength accelerating structures

Description: There is a growing interest in the development of high gradient ({ge} 1 GeV/m) accelerating structures. The need for high gradient acceleration based on current microwave technology requires the structures to be operated in the millimeter wavelength. Fabrication of accelerating structures at millimeter scale with sub-micron tolerances poses great challenges. The accelerating structures impose strict requirements on surface smoothness and finish to suppress field emission and multipactor effects. Various fabrication techniques based on conventional machining and micromachining have been evaluated and tested. These will be discussed and measurement results presented.
Date: November 1, 1996
Creator: Chou, P.J.; Bowden, G.B. & Copeland, M.R.
Partner: UNT Libraries Government Documents Department

Developing enabling optics finishing technologies for the National Ignition Facility

Description: Lawrence Livermore National Laboratory is in the process of constructing the National Ignition Facility, a half million square foot facility which will house a 192 beam laser system capable of generating the 2 million joules of ultraviolet light energy necessary to achieve fusion ignition with inertial targets by 2004. More than 7,000 meter class optics will need to be manufactured by LLNL`s industrial partners to construct the laser system. The components will be manufactured starting in 1998 and will be finished by 2003. In 1994 it became clear through a series of funded cost studies that, in order to fabricate such an unprecedented number of large precision optics in so short a time for the lowest possible cost, new technologies would need to be developed and new factories constructed based on those technologies. At that time, LLNL embarked on an ambitious optics finishing technology development program costing more than $6M over 3 years to develop these technologies, working with three suppliers of large precision optics. While each development program centered upon the specialties and often proprietary technologies already existing in the suppliers facility, many of the technologies required for manufacturing large precision optics at the lowest cost possible are common to two and in some cases all three efforts. Since many of the developments achieved during this program stemmed from intellectual property and trade secrets at the vendors, the program cannot be described completely in a public forum. Nevertheless, many non-proprietary advances were made during this program which the vendors are willing to share with the greater community. This presentation will describe the manufacturing process in a general sense which is used by all three of the companies under contract; Zygo Corporation, Tinsley Laboratories, and Eastman Kodak. In each of the principle process steps of shaping, grinding, polishing, figuring, and ...
Date: January 8, 1998
Creator: Aikens, D.M.; Rich, L.; Bajuk, D. & Slomba, A.
Partner: UNT Libraries Government Documents Department

Laser Induced Material Modification in the Bulk KDP Crystals

Description: Laser induced material modifications in the bulk and on the surface of KDP (KH{sub 2}PO{sub 4}) and DKDP (70-80% deuterated KDP) are studied using fluorescence imaging and spectroscopy. Photoluminescence is observed at damaged regions following above threshold exposure with an emission peak centered at 550-nm. In addition, surfaces exposed to >100 high power, 355-nm laser pulses reveal a reduced surface finishing quality as evidenced by an associated emission under UV photoexcitation. The emission spectra from the laser-induced damage sites and the laser degraded surfaces are similar suggesting the generation of similar defect species.
Date: December 16, 1999
Creator: Radousky, H.B.; Staggs, M.; Runkel, M. & Burnham, A.
Partner: UNT Libraries Government Documents Department

Performance evaluation of bound diamond ring tools

Description: LLNL is collaborating with the Center for Optics Manufacturing (COM) and the American Precision Optics Manufacturers Association (APOMA) to optimize bound diamond ring tools for the spherical generation of high quality optical surfaces. An important element of this work is establishing an experimentally-verified link between tooling properties and workpiece quality indicators such as roughness, subsurface damage and removal rate. In this paper, we report on a standardized methodology for assessing ring tool performance and its preliminary application to a set of commercially-available wheels. Our goals are to (1) assist optics manufacturers (users of the ring tools) in evaluating tools and in assessing their applicability for a given operation, and (2) provide performance feedback to wheel manufacturers to help optimize tooling for the optics industry. Our paper includes measurements of wheel performance for three 2-4 micron diamond bronze-bond wheels that were supplied by different manufacturers to nominally- identical specifications. Preliminary data suggests that the difference in performance levels among the wheels were small.
Date: July 14, 1995
Creator: Piscotty, M.A.; Taylor, J.S. & Blaedel, K.L.
Partner: UNT Libraries Government Documents Department

Hand deburring: a necessity that can be improved

Description: Hand deburring is a necessity that many companies perform either on a part-time or a full-time basis. Although hand deburring cannot be totally eliminated, an in-depth look at company approaches to this problem can result in significant savings. This paper highlights some of the problem areas and solutions for this facet of deburring.
Date: January 1, 1977
Creator: Johannesen, R.W.; Gillespie, L.K. & McMillen, J.L.
Partner: UNT Libraries Government Documents Department

precision deburring using NC and robot equipment. Final report

Description: Deburring precision miniature components is often time consuming and inconsistent. Although robots are available for deburring parts, they are not precise enough for precision miniature parts. Numerical control (NC) machining can provide edge break consistencies to meet requirements such as 76.2-..mu..m maximum edge break (chamfer). Although NC machining has a number of technical limitations which prohibits its use on many geometries, it can be an effective approach to features that are particularly difficult to deburr.
Date: May 1, 1980
Creator: Gillespie, L.K.
Partner: UNT Libraries Government Documents Department

Training for the deburring of precision miniature parts

Description: Formal training in deburring is significant because it is so rare. This lack is particularly evident when one must obtain or train individuals who can finish sophisticated parts to exacting edge requirements. The paper describes the training program developed by one large company. The program is based on the production of sophisticated precision miniature parts requiring high levels of precision and care. The format of the training program and considerations involved are described.
Date: May 1, 1979
Creator: Gillespie, L.K. & Bolinger, J.C.
Partner: UNT Libraries Government Documents Department

Deburring small intersecting holes

Description: Deburring intersecting holes is one of the most difficult deburring tasks faced by many industries. Only 14 of the 37 major deburring processes are applicable to most intersecting hole applications. Only five of these are normally applicable to small or miniature holes. Basic process capabilities and techniques used as a function of hole sizes and intersection depths are summarized.
Date: August 1, 1980
Creator: Gillespie, L.K.
Partner: UNT Libraries Government Documents Department

An Overview of Surface Finishes and Their Role in Printed Circuit Board Solderability and Solder Joint Performance

Description: A overview has been presented on the topic of alternative surface finishes for package I/Os and circuit board features. Aspects of processability and solder joint reliability were described for the following coatings: baseline hot-dipped, plated, and plated-and-fused 100Sn and Sn-Pb coatings; Ni/Au; Pd, Ni/Pd, and Ni/Pd/Au finishes; and the recently marketed immersion Ag coatings. The Ni/Au coatings appear to provide the all-around best option in terms of solderability protection and wire bondability. Nickel/Pal ftishes offer a slightly reduced level of performance in these areas that is most likely due to variable Pd surface conditions. It is necessmy to minimize dissolved Au or Pd contents in the solder material to prevent solder joint embrittlement. Ancillary aspects that included thickness measurement techniques; the importance of finish compatibility with conformal coatings and conductive adhesives; and the need for alternative finishes for the processing of non-Pb bearing solders were discussed.
Date: October 15, 1998
Creator: Vianco, P.T.
Partner: UNT Libraries Government Documents Department

A procedure for diamond turning KDP crystals

Description: A procedure and the equipment necessary for single-point diamond flycutting (loosely referred to as diamond turning) potassium di-hydrogen phosphate (KDP) crystals are described. It is based on current KDP diamond turning activities at the Lawrence Livermore National Laboratory (LLNL), drawing upon knowledge from the Nova crystal finishing development during the 1980`s and incorporating refinements from our efforts during 1995. In addition to describing a step-by-step process for diamond turning KDP, specific discussions are included on the necessary diamond tool geometry and edge sharpness, cutting fluid, and crystal preparation, handling, cleaning, and inspection. The authors presuppose that the reader is already familiar with diamond turning practices.
Date: July 7, 1995
Creator: Montesanti, R.C. & Thompson, S.L.
Partner: UNT Libraries Government Documents Department

Precision deburring of miniature parts. Final report

Description: An investigation of the capabilities of 35 deburring processes has aided in defining techniques for minimizing burr-related problems for the assurance of part-edge sharpness in the production of components for miniature precision mechanisms. Approaches for maintaining the required part-edge quality consist of utilizing available methods for preventing the formation of burrs, minimizing burr size by using proper machining conditions, designing parts to minimize deburring problems, and defining and extending the capabilities of existing deburring techniques.
Date: June 1, 1977
Creator: Gillespie, L. K.
Partner: UNT Libraries Government Documents Department

Crush Grinding

Description: Crush Grinding is a special process used at the Kansas City Plant to finish stem sections of reservoir products. In this process, a precise profile of the desired product is formed on a tungsten carbide roll. This roll slowly transfers a mirror image of the profile onto the grinding surface of a wheel. The transfer rate of the profile is between 0.001 and 0.010 inches per minute. Crush grinding is desirable since it provides consistent surface finishes and thin walls at a high production rate. In addition, it generates very sharp fillet radii. However, crush grinding is a complex process since many variables affect the final product. Therefore, the process requires more attention and knowledge beyond basic metal removal practices. While the Kansas City Plant began using these machines in 1995, a formal study regarding crush grinding has not been conducted there. In addition, very little literature is available in the grinding industry regarding this process. As a result, new engineers at the Kansas City Plant must learn the process through trial and error. The purpose of this document is to address this literature deficit while specifically promoting a better understanding of the stem crush grinding process at the Kansas City Plant.
Date: April 1, 2005
Creator: Nguyen, T. Q.
Partner: UNT Libraries Government Documents Department

Automation tools for flexible aircraft maintenance.

Description: This report summarizes the accomplishments of the Laboratory Directed Research and Development (LDRD) project 26546 at Sandia, during the period FY01 through FY03. The project team visited four DoD depots that support extensive aircraft maintenance in order to understand critical needs for automation, and to identify maintenance processes for potential automation or integration opportunities. From the visits, the team identified technology needs and application issues, as well as non-technical drivers that influence the application of automation in depot maintenance of aircraft. Software tools for automation facility design analysis were developed, improved, extended, and integrated to encompass greater breadth for eventual application as a generalized design tool. The design tools for automated path planning and path generation have been enhanced to incorporate those complex robot systems with redundant joint configurations, which are likely candidate designs for a complex aircraft maintenance facility. A prototype force-controlled actively compliant end-effector was designed and developed based on a parallel kinematic mechanism design. This device was developed for demonstration of surface finishing, one of many in-contact operations performed during aircraft maintenance. This end-effector tool was positioned along the workpiece by a robot manipulator, programmed for operation by the automated planning tools integrated for this project. Together, the hardware and software tools demonstrate many of the technologies required for flexible automation in a maintenance facility.
Date: November 1, 2003
Creator: Prentice, William J.; Drotning, William D.; Watterberg, Peter A.; Loucks, Clifford S. & Kozlowski, David M.
Partner: UNT Libraries Government Documents Department

Economic tradeoffs in deburring

Description: The reliability of small precision mechanisms depends on the production of burr-free, sharp-edged parts. An investigation was conducted to determine how these requirements could best be maintained. The study included investigating the capabilities of the 24 major deburring processes and finding other techniques for minimizing burr-related problems and assuring sharp-edged parts. It has been concluded that four approaches can be used to provide the required quality: prevent burrs from forming; minimize burr size by proper machining conditions; design parts to minimize deburring problems; and improve existing deburring techniques by defining and increasing capabilities.
Date: September 1, 1976
Creator: Gillespie, L. K.
Partner: UNT Libraries Government Documents Department

Effect of panel alignment and surface finish on bond strength

Description: The flexural strength of bonded acrylic is tested as a function of panel alignment and bond surface finish. Bond strength was shown to be highly dependent on both parameters with only a narrow range of values yielding a high strength bond. This study was performed for the heavy water-containing acrylic vessel for the Sudbury Neutrino Observatory detector.
Date: October 1, 1991
Creator: Wouters, J. M.; Doe, P. J. & Baker, W. E.
Partner: UNT Libraries Government Documents Department

Specifying the surface finish of x-ray mirrors

Description: Our measurements of x-ray mirrors at Brookhaven indicate that the power spectral densities of their finish errors have inverse power-law or fractal forms, rather than being flat at low frequencies as is usually assumed. This paper reviews these data and discusses how this apparent divergent behavior leads to finite but unconventional effects in imaging. Results are then used to develop more rational and realistic surface-finish specifications.
Date: December 31, 1993
Creator: Church, E. L. & Takacs, P. Z.
Partner: UNT Libraries Government Documents Department