Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Institution
- Keyword
-
- Ball Bonding (1)
- Dense Metallic Parts (1)
- Deposition Process (1)
- Flow Patterns (1)
- Laser Metal Deposition (1)
-
- Lead free solder (1)
- Materials preparation (1)
- Metal clusters (1)
- Nanostructured materials (1)
- Optoelectronics Packaging (1)
- Porosity (1)
- Porous materials (1)
- Powder Stream (1)
- Quantum wires (1)
- Reliability (1)
- Review (1)
- Surface reconstruction (1)
- Thermal conductivity (1)
- Transmission electron microscopy (1)
- Wedge Bonding (1)
- Wire Bonding (1)
Articles 1 - 14 of 14
Full-Text Articles in Manufacturing
Lead-Free Solder Joint Reliability – State Of The Art And Perspectives, Jianbiao Pan, Jyhwen Wang, David M. Shaddock
Lead-Free Solder Joint Reliability – State Of The Art And Perspectives, Jianbiao Pan, Jyhwen Wang, David M. Shaddock
Industrial and Manufacturing Engineering
There is an increasing demand in replacing tin-lead (Sn/Pb) solders with lead-free solders in the electronics industry due to health and environmental concern. The European Union recently passed a law to ban the use of lead in electronic products. The ban will go into effect in July of 2006. The Japanese electronics industry has worked to eliminate lead from consumer electronic products for several years. Although currently there are no specific regulations banning lead in electronics devices in the United States, many companies and consortiums are working on lead-free solder initiatives including Intel, Motorola, Agilent Technologies, General Electric, Boeing, NEMI …
Work Flow Policy And Within-Worker And Between-Workers Variability In Performance, Kenneth Howard Doerr, Tali Freed, Terence R. Mitchell, Chester A. Schriesheim, Xiaohua Zhou
Work Flow Policy And Within-Worker And Between-Workers Variability In Performance, Kenneth Howard Doerr, Tali Freed, Terence R. Mitchell, Chester A. Schriesheim, Xiaohua Zhou
Industrial and Manufacturing Engineering
Work flow policies are shown to induce a change in average between-workers variability (worker heterogeneity) and within-worker variability in performance times. In a laboratory experiment, the authors measured the levels of worker heterogeneity and within-worker variability under an individual performance condition, a work sharing condition, and a fixed assignment condition. The work sharing policy increased the levels of worker heterogeneity and worker variability, whereas the fixed assignment policy decreased them. These effects, along with work flow policy main effects on mean performance times and variability are examined. This article represents an initial step in understanding effects that may be important …
Modeling Of The Metal Powder Flow With Carrier Gas In Coaxial Nozzle For Direct Laser Deposition Process, Heng Pan, Frank W. Liou
Modeling Of The Metal Powder Flow With Carrier Gas In Coaxial Nozzle For Direct Laser Deposition Process, Heng Pan, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
In direct laser deposition process, metal powder is directly fed with carrier gas through the coaxial nozzle into the melt pool created by the laser to form the solid parts. Many operational parameters of the process depend on the characteristic of the powder stream structure below the exit of the coaxial nozzle. In this paper, a computational approach is developed for the simulation of the gas-particle flow in the coaxial nozzle. By taking into account the nozzle geometry and operating parameters, such as width and inclination angle of powder passage and carrier gas velocity, the developed computational code allows the …
Study Of Ceramic Slurries For Investment Casting With Ice Patterns, Qingbin Liu, Ming-Chuan Leu, Harish Jose, Von Richards
Study Of Ceramic Slurries For Investment Casting With Ice Patterns, Qingbin Liu, Ming-Chuan Leu, Harish Jose, Von Richards
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Ice patterns generated by rapid freeze prototyping or a molding process can be used to make ceramic investment molds for metal castings. Due to the use of ice, the ceramic slurries must be poured around the pattern and cured at sub-freezing temperatures. Success of this process depends greatly on the mold strength after the gelation of the slurries. This paper describes the experimental results of the mold strength after the gelation of the slurries under different compositions. The parameters considered include mixing time, alumino-silicate vs. fused silica ratio, volume of binder, and volume of catalyst. The strength of the gelled …
Numerical And Experimental Analysis Of The Powder Flow Streams In The Laser Aided Material Deposition Process, Yogesh D. Thakar, Heng Pan, Frank W. Liou
Numerical And Experimental Analysis Of The Powder Flow Streams In The Laser Aided Material Deposition Process, Yogesh D. Thakar, Heng Pan, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Axial powder stream concentration between the nozzle end and the deposition point is an important process parameter in the laser aided material deposition process. The powder concentration is greatly influenced by the nozzle geometry in use. This paper describes the numerical and experimental analysis of this important parameter in relation to the coaxial nozzle. The experiments are performed with the different nozzle geometries to generate various flow patterns of the gravity fed powder in a cold stream. The results of the experimental analysis are compared with the numerical simulation and found justified. These results are used in concluding the significance …
Development Of Image Processing Tools For Analysis Of Laser Deposition Experiments, Todd E. Sparks
Development Of Image Processing Tools For Analysis Of Laser Deposition Experiments, Todd E. Sparks
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Microscopical metallography is a well established field with a long history of techniques for measuring features. Modern computational power allows much more rigorous investigation than simple area fractions and intercept measurements. This paper details the development of image processing tools using GNU Octave, a free, open source numerical computation package. Proposed in the paper is a method for characterizing features within a digital microscope image.
Experimental Investigation Of Laser Metal Deposition Of Functionally Graded Copper And Steel, Vinay Kadekar, Sashikanth Prakash, Frank W. Liou
Experimental Investigation Of Laser Metal Deposition Of Functionally Graded Copper And Steel, Vinay Kadekar, Sashikanth Prakash, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Laser metal deposition is an emerging technology for producing fully dense metallic parts. This process shows a promising future for the deposition of functionally graded steel - copper alloys. Good thermal conductivity of copper and a high wear resistance of steel can be achieved in dies and cores. However, to accomplish this, there are many issues to be resolved, such as the formation of an undesirable phase, solidification cracking, porosity at the interface and difference in thermal coefficient of expansion between steel and copper. The influences of process variables, such as laser power, laser scan speed, composition, powder flow rate, …
Wire Bonding Challenges In Optoelectronics Packaging, Jianbiao Pan, Patrice Fraud
Wire Bonding Challenges In Optoelectronics Packaging, Jianbiao Pan, Patrice Fraud
Industrial and Manufacturing Engineering
Wire bonding has been used in integrated circuit (IC) packaging for many years. However, there are many challenges in wire bonding for optoelectronics packaging. These challenges include bonding on sensitive devices, bonding over cavity, bonding over cantilevel leads and bonding temperature limitations. The optoelectronics package design brings another challenge, which requires wire bonding to have deep access capability. In this paper, the wire bonding technologies are reviewed and ball bonding and wedge bonding are compared. The variables that affect the wire bonding process are then discussed. Finally, the challenges of wire bonding in optoelectronics packaging are presented in detail.
Effect Of Chromium-Gold And Titanium-Titanium Nitride-Platinum-Gold Metallization On Wire/Ribbon Bondability, Jianbiao Pan, Robert M. Pafchek, Frank F. Judd, Jason Baxter
Effect Of Chromium-Gold And Titanium-Titanium Nitride-Platinum-Gold Metallization On Wire/Ribbon Bondability, Jianbiao Pan, Robert M. Pafchek, Frank F. Judd, Jason Baxter
Industrial and Manufacturing Engineering
Gold metallization on wafer substrates for wire/ribbon bond applications require good bond strength to the substrate without weakening the wire/ribbon. This paper compares the ribbon bondability of Cr/Au and Ti/TiN/Pt/Au metallization systems. Both chromium and titanium are used to promote adhesion between substrates and sputtered gold films. Both can diffuse the gold surface after annealing and degrade the wire/ribbon bondability. Restoring bondability by ceric ammonium nitrate (CAN) etch was investigated. Experiments were conducted to investigate the effect of Cr/Au and Ti/TiN/Pt/Au, annealing, and CAN etch processes on 25.4 times; 254 μm (1 × 10 mil) ribbon bonding. All bonds were …
Pressure Distribution Around Spherical Distal Ball-Tip In Ultrasound Angioplasty, Graham Gavin, Garrett B. Mcguinness, Finbar Dolan, M.S. J. Hashmi
Pressure Distribution Around Spherical Distal Ball-Tip In Ultrasound Angioplasty, Graham Gavin, Garrett B. Mcguinness, Finbar Dolan, M.S. J. Hashmi
Conference Papers
INTRODUCTION Ultrasound Angioplasty has been shown to be effective in the removal and re-canalising of blockages in arteries (Siegel RJ, 1993). By delivering therapeutic ultrasound to the blockage, via a wire waveguide to a ball-tip, the lesion or thrombus is affected by pressure waves, micro streaming, cavitation and direct contact with the oscillating ball-tip. Most work to date has concentrated on a spherical ball-tip geometry at the distal end of the wire waveguide (Steffen, 1994 and Rosenschein, 1996). Tip displacements usually lie between 10 - 100m (peak-to peak) and ball tip diameters between 1 - 2mm (Atar, 1999 and Yock, …
Critical Variables Of Solder Paste Stencil Printing For Micro-Bga And Fine-Pitch Qfp, Jianbiao Pan, Gregory L. Tonkay, Robert H. Storer, Ronald M. Sallade, David J. Leandri
Critical Variables Of Solder Paste Stencil Printing For Micro-Bga And Fine-Pitch Qfp, Jianbiao Pan, Gregory L. Tonkay, Robert H. Storer, Ronald M. Sallade, David J. Leandri
Industrial and Manufacturing Engineering
Stencil printing continues to be the dominant method of solder deposition in high-volume surface-mount assembly. Control of the amount of solder paste deposited is critical in the case of fine-pitch and ultrafine-pitch surface-mount assembly. The process is still not well understood as indicated by the fact that industry reports 52-71% surface-mount technology (SMT) defects are related to the solder paste stencil printing process. The purpose of this paper is to identify the critical variables that influence the volume, area, and height of solder paste deposited. An experiment was conducted to investigate the effects of relevant process parameters on the amount …
A Supply Chain Management Tool For Linking Courses In Manufacturing Engineering , Daniel Waldorf, Sema E. Alptekin
A Supply Chain Management Tool For Linking Courses In Manufacturing Engineering , Daniel Waldorf, Sema E. Alptekin
Industrial and Manufacturing Engineering
A Recent Society of Manufacturing Engineers (SME) grant received by Manufacturing Engineering Program at Cal Poly has provided funds to strengthen its curricular focus on supply chain management, flexibility, business skills, quality, and process controls. New courses and laboratories are developed in electronics manufacturing, information technology, and supply chain management. A functioning supply chain environment has been developed to provide vertical integration among several courses. A software tool being developed in-house integrates the activities of the students who play the roles of customers and suppliers. Details of the various components of this comprehensive project are presented in this paper.
Understanding Manufacturing Energy Use Through Statistical Analysis, J. Kelly Kissock, John Seryak
Understanding Manufacturing Energy Use Through Statistical Analysis, J. Kelly Kissock, John Seryak
Mechanical and Aerospace Engineering Faculty Publications
Energy in manufacturing facilities is used for direct production of goods, space conditioning, and general facility support such as lighting. This paper presents a methodology for statistically analyzing plant energy use in terms of these major end uses. The methodology uses as few as 60 data points that are relatively easy for most plants to obtain. Multivariable change-point models of electricity and natural gas use as functions of outdoor air temperature and production data are then developed. The statistical models can be used to predict energy use for energy budgeting, measure savings, determine cost structures, and diagnostic purposes. Moreover, in …
Noble Metal Nanostructures Synthesized Inside Mesoporous Nanotemplate Pores, J. Arbiol, E. Rossinyol, A. Cabot, F. Peiró, A. Cornet, J. R. Morante, Fanglin Chen, Meilin Liu
Noble Metal Nanostructures Synthesized Inside Mesoporous Nanotemplate Pores, J. Arbiol, E. Rossinyol, A. Cabot, F. Peiró, A. Cornet, J. R. Morante, Fanglin Chen, Meilin Liu
Faculty Publications
Noble metal impregnation has resulted in the inclusion of metal nanostructures within the SBA-15 mesoporous silica hexagonal pores (from nanoclusters to nanowires). A bright-field transmission electron microscopy three-dimensional reconstruction is proposed to analyze the localization of nanostructures within the pores of mesoporous nanotemplates. The method allows corroboration whether the nanostructures are synthesized inside the pores or they are synthesized alternatively on the nanotemplate aggregates exterior surface.