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Extreme Low-Temperature High Strain-Rate Constitutive Behavior Evolution of Doped and Undoped Leadfree Solders under Sustained High Temperature Exposure

Extreme Low-Temperature High Strain-Rate Constitutive Behavi...

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Electronic Components and Technology Conference (ECTC)

作者： Pradeep Lall Vishal Mehta Vikas Yadav Mrinmoy Saha Jeff Suhling Dave Locker Department of Mechanical Engineering NSF-CAVE3 Electronics Research Center Auburn University Auburn AL Development Command CCDC-AvMC US Army Combat Capabilities Huntsville AL

Electronics in automotive under-hood and aerospace applications may require sustained high temperature exposure in the range of 150-200°C in addition to mechanical shock and vibration. Electronics may be stored for prolonged duration in non-climate-controlled enclosures prior to deployment in the end application. In addition, electronics may be subjected to high strain rates at extreme low temperature and high temperature extremes. The effect of sustained high temperature storage on the high strain rate low-temperature performance are not well understood. In this paper SAC305, SAC-Q, SAC-R, and M758 solder are studies in a strain-rate range of 1-100 per sec in the temperature range of -65°C to +200°C after 8-months of sustained exposure to 50°C and 100°C. Doped solder alloys include addition of Ni, Co, Au, P, Ga, Cu and Sb to SAC solder alloy to boost the mechanical properties, thermal properties, wettability, melting temperature, shock and drop performance and solder alloy microstructure. The accuracy of Anand model has been quantified by comparing the experimentally measured data with the predicted data with the computed model constants. The Anand parameters have been implemented in an FE-framework to simulate the drop events for a ball-grid array package on printed circuit board assembly to determine hysteresis loop and plastic work density. Evolution in hysteresis loops and PWD have been studied and compared for various thermal aging durations and storage temperatures in addition to extreme operating temperatures.

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Hybrid Integration of Semiconductor Lasers: Impact of Matching Laser AR Coatings to Photonic Wire Bonds

Hybrid Integration of Semiconductor Lasers: Impact of Matchi...

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CLEO: Applications and Technology in CLEO 2024, CLEO: A and T 2024 - Part of Conference on Lasers and Electro-Optics

作者： Esmaeeli, Omid Mitchell, Matthew Bickford, Justin Grillot, Frederic Chrostowski, Lukas Shekhar, Sudip Department of Electrical and Computer Engineering The University of British Columbia VancouverBC Canada Stewart Blusson Quantum Matter Institute The University of British Columbia VancouverBC Canada Dream Photonics Inc. VancouverBC Canada Army Research Laboratory US Army Combat Capabilities Development Command AdelphiMD United States LTCI Telecom Paris Institute Polytechnique de Paris Palaiseau91120 France Center for High Technology Materials University of New Mexico AlbuquerqueNM87106 United States Dream Photonics Inc. WoodinvilleWA United States

We investigate the influence of anti-reflection (AR) coating index on the performance of distributed feedback (DFB) lasers when integrated to a fiber using photonic wire bonds (PWBs). We compare the performance of air... 详细信息

关键词： Distributed feedback lasers

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Evolution of High-Temperature and Low-Temperature High Strain Rate Properties for SAC-R after Sustained Exposure to 50°C

Evolution of High-Temperature and Low-Temperature High Strai...

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Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITHERM)

作者： Pradeep Lall Mrinmoy Saha Jeff Suhling Ken Blecker Department of Mechanical Engineering NSF-CAVE3 Electronics Research Center Auburn University Auburn AL US Army Combat Capabilities Development Command Armament Center Picatinny Arsenal NJ

ISBN: (数字)9781665485036

ISBN: (纸本)9781665485043

Electronic parts in military, automotive, avionics and space applications may be subjected to sustained operation at high temperature in addition to high strain-rate loads. Parts may be stored in non-climate-controlled enclosures prior to deployment. Earlier studies on undoped SAC alloys have shown that the material properties evolve after prolonged period of storage at even modest temperatures. In order to mitigate the aging effects, a number of alloy formulation have been proposed. Data of the mechanical properties of lead-free solder alloys which is used for interconnection in the electronic packaging at high strain rates and at high storage temperature is very essential for design optimization of electronic package sustainability at extreme temperature environment because the SAC solders have shown to have degradation in mechanical properties at prolonged exposure to storage temperature. Industries have come up with a solution to reduce the degradation using dopants in SAC solder. In this study, a doped SAC solder called SAC-R (Ecolloy) has been subjected to high strain rate testing after keeping them in storage at temperature of 50°C for 1 - 8months. Samples with no aging and aged samples for up to 8-months have been subjected to uniaxial tensile tests to measure the mechanical properties of SAC-R for High and Low operating temperature ranging from -65°C to 200°C. The material data has been used to compute the constants for the Anand Visco-Plasticity model. The ability of the model to represent the material constitutive behavior has been quantified by comparing the model predictions of the uniaxial tensile test with the experimental data

关键词： Temperature measurement Degradation Temperature distribution Biological system modeling Computational modeling Predictive models Aging

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Effect of Evolution of High Strain Rate Properties on Plastic-Work of SAC305 Alloy with 100°C Aging for Periods up to 240-days

Effect of Evolution of High Strain Rate Properties on Plasti...

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Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITHERM)

作者： Pradeep Lall Vishal Mehta Jeff Suhling Ken Blecker Department of Mechanical Engineering NSF-CAVE3 Electronics Research Center Auburn University Auburn AL US Army Combat Capabilities Development Command Armament Center Picatinny Arsenal NJ

ISBN: (数字)9781665485036

ISBN: (纸本)9781665485043

In the industries related to aerospace applications, medical applications and in oil/gas exploration, the electronic components may have to face very cold to extreme high surrounding temperatures. In addition, these electronic packages and assemblies can be exposed to vibrations, shocks and impacts. In such severe surrounding, electronic components may face strain rates of 1 to 100 per seconds and low surrounding temperature down to -65°C. The records are not existing for lead-free solder alloys tested at extreme surrounding temperature and at high strain rates, with isothermal aging. Previous published results for SAC305 lead-free solder alloys is limited to low strain rates and high operating temperatures. In this paper, lead-free solder alloy SAC305 has been tested and studied at extreme surrounding temperature starting from -65°C up to 200°C, with high strain rates, with isothermal aging at 100°C for up to 240 days. The prepared SAC305 lead-free alloy specimen after reflowing, were stored for thermal aging and then tested at strain rates of 10, 35, 50, and 75 per sec. at multiple operating temperatures ranging from -65°C to 200°C. Stress-strain curves are generated for various operating temperatures and for the range of strain rates. The experimental data has been fit to the Anand Viscoplasticity model for SAC305 and the Anand constants are established by predicting the measured stress-strain behavior for the various surrounding temperatures and high strain rates, for aging durations up to 240 days (i.e. 8 months). Also, FE analysis has been carried out for drop/shock events for BGA package assembly with PCB. Hysteresis stress-strain curves and plastic work density curves are generated for various aging conditions for SAC305 solder ball joints.

关键词： Temperature measurement Vibrations Temperature distribution Thermomechanical processes Electronic components Aging Lead

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High Strain Rate Mechanical Properties of M758 Solder at Extreme Surrounding Temperatures, with 100°C Isothermal Aging for up to 180 Days

High Strain Rate Mechanical Properties of M758 Solder at Ext...

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Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITHERM)

作者： Pradeep Lall Vishal Mehta Jeff Suhling Ken Blecker Department of Mechanical Engineering Auburn University NSF-CAVE3 Electronics Research Center Auburn AL US Army Combat Capabilities Development Command - Armament Center Picatinny Arsenal NJ

ISBN: (数字)9781665485036

ISBN: (纸本)9781665485043

In the industries related to automotive, oil and gas, aerospace, medical technologies, electronic parts can often be exposed to high strain loads during shocks, vibrations and drop-impact conditions. Such electronic parts can often face the extreme low and high temperatures ranging from -65°C to 200°C. Additionally, these electronic devices can be subjected to strain rates of 1 to 100/sec in the critical environment. Lately, numerous doped solder alloys are being introduced in the electronic component e.g. SAC-Q, SAC-R, Innolot, etc. M758 is a novel general purpose, thermal fatigue resistant doped solder alloy, used for surface mount technology. Mechanical characteristic results and data for lead-free solder alloys are extremely important for optimizing electronic package reliability, at high temperature storage and elevated strain rates. Moreover, the mechanical properties of solder alloys can be transformed considerably due to the thermal aging, which is causing alteration of microstructure. Statistics for the mechanical properties of M758 solder alloy with an extreme low to high operating temperatures, with thermal aging effects are not available. In this work, M758 doped solder material is tested and studied for this study at range of operating temperatures of -65°C to 200°C and at a strain rate up to 75/sec for up to 180 days (i.e. 6 months) of isothermal aging with storage temperature of 100°C. For the extensive range of strain rates and surrounding test temperatures, stress-strain curves are established. Additionally, the measured experimental results and data were fitted to the Anand viscoplasticity model and the Anand constants were calculated by estimating the stress-strain behavior measured for operating temperatures -65°C to 200°C. Also, FE analysis has been carried out for drop/shock events for BGA package assembly with PCB. Hysteresis stress-strain curves and plastic work density curves are generated for various aging conditions for M758 solder ball jo

关键词： Temperature measurement Vibrations Temperature distribution Thermomechanical processes Aging Electronic packaging thermal management Iron

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Chemical Ignition Behavior and Data-Driven Modeling of Alternative Alcohol-to-Jet (ATJ) Fuel

SSRN

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SSRN 2022年

作者： Kim, Keunsoo Ryu, Je Ir Lee, Wooyoung Wiersema, Paxton Mayhew, Eric Temme, Jacob Kweon, Chol-Bum M. Lee, Tonghun Department of Mechanical Science and Engineering University of Illinois at Urbana-Champaign UrbanaIL61801 United States Weapons and Materials Research Directorate U.S. Army Combat Capabilities Development Command Army Research Laboratory Aberdeen Proving Ground MD21005 United States Computational and Information Sciences Directorate U.S. Army Combat Capabilities Development Command Army Research Laboratory Aberdeen Proving Ground MD21005 United States

This work assesses the chemical ignition delay behavior of an isoparaffinic alcohol-to-jet (ATJ) fuel, one of the certified sustainable aviation fuels (SAFs). We performed the chemical ignition delay measurements of ATJ at a compressed pressure of PC = 2 MPa and three equivalence ratios (=0.5, 1.0, & 1.3) in synthetic dry air, between 667 K and 1250 K. The unique chemical structures of isoalkanes result in high thermal decomposition rate, but low chemical oxidation reactivity. The new lumped mechanism (ARLMech-HC-ATJ) is developed using a genetic algorithm based on empirical ignition delays. The mechanism shows good performance over the temperature range from 667K to 1250 K and varied equivalence ratios. Using the suggested mechanism, this study presents sensitivity analysis for the temperature range as well as two combustion simulations to demonstrate application to practical systems. The results show the impact of using ATJ modeling to design and optimize propulsion systems operating in the negative temperature coefficient (NTC) or low temperature chemistry (LTC) regime in the future and a methodology that can be adapted to other novel fuels. © 2022, The Authors. All rights reserved.

关键词： Temperature

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A Novel Approach to Non-Intrusive Estimation of In-Cylinder Pressure and Combustion Parameters Using an External Accelerometer

SSRN

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SSRN 2022年

作者： Rajamani, Rajesh Jeon, Woongsun Georgiou, Anastasis Sun, Zongxuan Rothamer, David A. Kim, Kenneth Kweon, Chol-Bum School of Electrical and Electronics Engineering Chung-Ang University Seoul06974 Korea Republic of Department of Mechanical Engineering University of Minnesota MinneapolisMN55455 United States Department of Mechanical Engineering University of Wisconsin-Madison MadisonWI53706 United States Army Research Laboratory United States Combat Capabilities Development Command's Army Research Laboratory

This paper develops a new approach to estimation of in-cylinder pressure and combustion variables in a diesel engine using measurements from a non-intrusive accelerometer. The new estimation approach is based on separating the combustion component of the acceleration signal from the non-combustion component. Only the combustion component of the acceleration is well correlated with the combustion component of in-cylinder pressure. A first order differential equation model between these combustion components is proposed and used to estimate in-cylinder pressure. The combustion component of acceleration is obtained by using a finite impulse response model and a real-time adaptive least squares algorithm that utilizes the crankshaft speed signal to find and subtract the speed-related component of the acceleration measurement. The proposed method is evaluated experimentally using a turbocharged high speed 4-cylinder compression-ignition direct-injection (CIDI) engine and over 85 data sets of different operating conditions involving both single and double (pilot and main) injections. © 2022, The Authors. All rights reserved.

关键词： Accelerometers

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Multi-Task Multi-Fidelity Learning of Properties for Energetic Materials

arXiv

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arXiv 2024年

作者： Appleton, Robert J. Klinger, Daniel Lee, Brian H. Taylor, Michael Kim, Sohee Blankenship, Samuel Barnes, Brian C. Son, Steven F. Strachan, Alejandro School of Materials Engineering Birck Nanotechnology Center Purdue University West LafayetteIN47907 United States School of Mechanical Engineering Purdue University West LafayetteIN47907 United States Department of Mechanical Engineering New Mexico Institute of Mining and Technology SocorroNM87801 United States Department of Computer Sciences Purdue University West LafayetteIN47907 United States U.S. Army Combat Capabilities Development Command Army Research Laboratory Proving Ground AberdeenMD21005 United States

Data science and artificial intelligence are playing an increasingly important role in the physical sciences. Unfortunately, in the field of energetic materials data scarcity limits the accuracy and even applicability of ML tools. To address data limitations, we compiled multi-modal data: both experimental and computational results for several properties. We find that multi-task neural networks can learn from multi-modal data and outperform single-task models trained for specific properties. As expected, the improvement is more significant for data-scarce properties. These models are trained using descriptors built from simple molecular information and can be readily applied for large-scale materials screening to explore multiple properties simultaneously. This approach is widely applicable to fields outside energetic materials. © 2024, CC BY.

关键词： Data Science

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Three rotor hub flow prediction workshops (2016-2020) - What did we learn & What's next ? 77

Three rotor hub flow prediction workshops (2016-2020) - What...

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77th Annual Vertical Flight Society Forum and Technology Display: The Future of Vertical Flight, FORUM 2021

作者： Schmitz, Sven Tierney, Charles Reich, David Jaffa, Nicholas Centolanza, Louis R. Thomas, Mathew L. Dept. of Aerospace Engineering Pennsylvania State University University ParkPA16802 United States Applied Research Laboratory Pennsylvania State University University ParkPA16802 United States U.S. Army Combat Capabilities Development Command Aviation Missile Center Fort EustisVA23604 United States

ISBN: (纸本)9781713830016

The 'Rotor Hub Flow Prediction Workshops' have been productive collaborations between experimental and computational efforts in the important area of high-Reynolds number model testing of rotor hubs and associated complex interactional aerodynamics in the long-age wake as relevant to current and future rotorcraft. As such the hub flow workshops have joined the ranks of past successful collaborations such as the UH-60 Airloads and HART-II workshops. This paper begins by describing the basic physics of rotor hub flows and gives a brief summary of recent water-tunnel test campaigns. Following, the evolution of the hub flow workshops is summarized, with emphasis on the productive interactions between experimentalists and computational participants. A compilation of computational blind comparison results against measured data for all three workshops thus far is presented. Challenges associated with uncertainties in both experiments and computations and their effect on quantitative comparisons are discussed. In particular, emphasis is given to the 'Lessons Learned' on both sides and an outlook into remaining challenges and next research steps in the area of rotor hub flows is provided. © 2021 by the Vertical Flight Society.

关键词： Reynolds number

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Electrodeposition of Pyrolyzed Structured Carbon for 3d Printed Electronics

SSRN

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SSRN 2023年

作者： Tyler, Joshua B. Smith, Gabriel L. Cumings, John Lazarus, Nathan Oak Ridge Associated Universities United States The University of Maryland Department of Materials Science and Engineering College ParkMD20742 United States U.S. Army Combat Capabilities Development Command – Army Research Laboratory 2800 Powder Mill Rd AdelphiMD20783 United States The University of Delaware Electrical and Computer Engineering Department 210 South College Ave NewarkDE19716 United States

3D printing of conductive materials has the ability to unlock arbitrary complex designs for electronic device fabrication. Through thermal decomposition (pyrolysis) of vat photopolymerized 3D printed parts, a structured conductive amorphous carbon device can be manufactured;however, the conductivity of the pyrolyzed carbon material is orders of magnitude lower than metals. In this work, we demonstrate the ability to metallize pyrolyzed 3D printed carbon devices using electrodeposition of bulk metals. Pyrolysis of vat photopolymerized printed parts was performed in a vacuum furnace at 900 °C to achieve a conductive carbon material with a conductivity of 9.26×104 S m-1. Electroplating is demonstrated to metalize the devices with either copper or nickel, increasing the effective conductivity of the parts by 168X and 104X, respectively. Soldering to the electrodeposited films showed the ease at which this hybrid material can be electrically integrated. Moreover, the solder joint was demonstrated to be more mechanically robust than the metallized carbon material. Further investigation into the mechanical properties of the carbon material before and after plating with nickel show that by electrodepositing 10 µm of nickel onto the surface of the carbon we achieve an increase in fracture stress of ~32% and a more than 2X increase in the effective Young’s modulus. By increasing the conductivity and solderability of vat photopolymerized pyrolyzed carbon through electroplating we were able to demonstrate component embedding of an LED circuit, showing future potential in incorporating the plated material into electrical systems. © 2023, The Authors. All rights reserved.

关键词： Nickel

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