APRIL 2026 NEWSLETTER

CALCE Webinar: Harmonic-Vibration Durability of Low Temperature Solders

Jonathan Martin, a graduate student of Prof. Abhijit Dasgupta, will present a webinar, “Harmonic-Vibration Durability of Low Temperature Solders,” on Tuesday, May 12, 2026, at 11:00 a.m. US Eastern on Zoom. His talk will focus on how different low-temperature solder alloys perform under harmonic vibration testing, comparing their durability with SAC305 and highlighting findings from fatigue modeling, finite element analysis, and interconnect reliability studies for next-generation electronic assemblies.

Register here.

IMAPS Chesapeake and UMD Student Chapter Meeting

The Chesapeake Chapter of IMAPS, which includes members from Northern Virginia, Washington, D.C., Maryland, and Delaware, is hosting an event in collaboration with the University of Maryland student chapter. Prof. Patrick McCluskey will open the program, followed by remarks from local and UMD student chapter leadership, and features technical presentations by Prof. Damena Agonafer and Dr. David Shahin on advanced cooling technologies and onshore advanced Packaging at Northrop Grumman. The event also includes a 3-Minute Thesis segment highlighting student research, and concludes with an IMAPS business meeting and networking opportunity.

Register here.

Professional Development Courses at CALCE/SMTA Counterfeit Symposium

At the 2026 SMTA/CALCE Symposium on Counterfeit Parts and Materials, a full day of professional development courses will be offered on June 25, 2026. The courses are: “Understanding and Implementing Industry Standards for Counterfeit Avoidance”,  “How to Make the Best Use of 2026 Updates to SAE AS6171,” and “Electronic Part Obsolescence Forecasting, Mitigation, and Management.”

Dr. Diganta Das

Understanding and Implementing Industry Standards for Counterfeit Avoidance

Dr. Michael Azarian

How to Make the Best Use of 2026 Updates to SAE AS6171

Prof. Peter Sandborn

Electronic Part Obsolescence Forecasting, Mitigation, and Management

Speakers Announced for CALCE/SMTA Counterfeit Symposium

This year’s technical program will include counterfeit avoidance and testing standards, applications of AI in inspection and tracking, decision-making regarding counterfeit, and more. The symposium will also include two panel discussions: one focused on the new SAE 6171 counterfeit detection standard suite and its expanded tools and defect coverage, and another examining the renewed challenge of component allocations and long lead times in the distribution industry.

CALCE Seminar: Failure Investigation of the First Large Lithium-ion Battery Used in Aircraft

Dr. Judy Jeevarajan, Vice President and Executive Director of the Electrochemical Safety Research Institute at UL Research Institutes, will deliver a talk titled “Failure Investigation of the First Large Lithium-ion Battery Used in Aircraft” on Monday, April 27, 2026, at 11:00 a.m., her lecture will discuss the thermal runaway incidents involving the first large lithium-ion batteries used in commercial aircraft, the investigation conducted into those failures, and the probable causes behind them. The lecture will cover cell and battery design, the failure investigation carried out, and will provide a summary of the probable causes of the failure. It will highlight how environmental conditions, combined with technical factors, contributed to the failures and shaped the investigation findings.

Professor Michael Pecht to Deliver Plenary Address at International Conference on System Reliability and Safety

Professor Michael Pecht, Director of the Center for Advanced Life Cycle Engineering (CALCE) at the University of Maryland, will deliver a plenary talk at the International Conference on System Reliability and Safety (ICSRS) from November 23-25, 2026, in Rome, Italy. On the occasion of the 10th anniversary of ICSRS, his presentation, titled "Predicting Electronics Reliability: What the Best Companies are Doing," will explore how top companies combine reliability science with machine learning and data analytics to predict and improve electronics reliability.

In his talk, Professor Pecht will address a growing concern in industry: new technologies are often rushed to market before their reliability is fully proven. He will explain how such decisions can result in costly recalls, increased maintenance demands, and dissatisfied customers. be used more effectively.

Prof. Siddhartha Das Earns AES Electrophoretic Society Mid-Career Achievement Award

Professor Siddhartha Das is the 2026 recipient of the AES Electrophoretic Society Mid-Career Achievement Award, which recognizes exceptional contributions to electrophoresis, microfluidics, and related fields. AES announced the award recently on LinkedIn.

Prof. Das received the award in honor of his research concerning flows of liquids and ions in soft nanochannels, which are nanochannels grafted with charged polymer chains. The award will be conferred officially at the annual SciX Conference, scheduled for October 4-9 in Reno, NV. During that event, Das will deliver a plenary award talk and lead a special session featuring invited speakers.

University of Maryland Hosts NASA Parts Engineering Program Event

On April 2, CALCE at the University of Maryland hosted a kickoff meeting that brought together leaders from academia, government, and industry to discuss electronic parts engineering and the future of the electronics supply chain in the context of the NASA Parts Engineering Program. The program included participation from Auburn University and the University of Central Florida, as well as representatives from NASA (JPL and GSFC), Lockheed Martin, John Deere, and other industry sectors.

A Review of Float Charging in Lithium-Ion Batteries: Degradation Mechanisms, Influencing Factors, and Optimization Strategies

Lithium-ion batteries (LIBs) are increasingly being used in backup energy storage applications such as on-grid substations and solar systems, where maintaining a full state of charge is essential to ensure immediate availability and delivery of rated capacity. As a result, float charging, which involves supplying a low, continuous current to maintain the battery's charged potential and counteract self-discharge, is used to ensure batteries remain fully charged. However, prolonged float charging can lead to battery degradation caused by electrolyte decomposition, deposition of metallic lithium, and structural changes of the electrodes, compromising battery lifespan, performance, and safety.

Reliability Analysis of a Microinverter Prototype: A Case Study on Sn-Ag-Cu Solder Under Thermal Fatigue for Encapsulated GaN Packages

A single-stage dual-active-bridge direct current-alternating current (DC-AC) micro-inverter prototype with Gallium Nitride (GaN) primary switching devices was assembled and subjected to environmental reliability testing. Testing consisted of an unpowered temperature cycling with an amplitude ranging from −40 °C to 105 °C. Electrical performance characterization was performed during the accelerated testing at regular intervals until a failure was observed. Nondestructive failure analysis was performed on the board to determine the failure modes and mechanisms, and it revealed that the failure occurred due to solder bump delamination at the gate, source, and drain pads.

Novel Test Method to Measure Time-cure Superposition Shift Factors of Filled-Thermoset Under Isocure Testing Conditions

Despite the solid theoretical foundation of time-cure superposition, the time-cure superposition (TCS) shift factors reported in the literature do not support the theory very well. The discrepancy stems from the non-isocure test conditions used in the tests. This study proposes a novel method to eliminate the inherent problems of existing techniques to measure the TCS shift factors, i.e., to measure them under isocure test conditions. The proposed method optimizes a test procedure while offering sufficient relaxation but producing no or negligible additional curing during testing. Optimization requires a complete understanding of curing behavior, not only in the chemically-controlled domain but also in the diffusion-controlled domain. …

Impact-Based Maintenance Efficiency Modeling for Multi-Component Systems with Condition-Based Component Selection

This paper develops an impact-based maintenance efficiency model that dynamically links maintenance effectiveness to the number and criticality of replacement components in multi-component repairable systems. Unlike existing approaches that assume static efficiency parameters, the model enables maintenance decisions that adapt to actual system degradation states. The efficiency formulation decomposes into a risk fraction capturing the proportion of weighted system degradation addressed, and a coverage factor with a diminishing-returns parameter reflecting the criticality distribution of maintained components.

A Meta-Transfer Learning-Guided Approach for Remaining Useful Life Prediction of Rolling Bearings with Small-Sample Data

As a key transmission component of rotating machinery, the life prediction and health management of rolling bearings are crucial for achieving intelligent operation and maintenance of equipment and ensuring the reliability of the system. A small-sample remaining useful life (RUL) prediction approach for rolling bearings based on meta-transfer learning is proposed in this paper. By fusing model-agnostic meta-learning (MAML) and domain adversarial neural networks (DANN), a MAML-DANN transfer learning (MDTL) framework is constructed to address the dual challenges of few-shot adaptation and cross-domain alignment. …

Hierarchical Hollow Silica Shells for Scalable and Passive Superinsulation

Porous silica materials are highly valued for their thermal management potential, with their high porosity and large surface area making them ideal for insulation. However, challenges persist in their practical manufacturing and in establishing clear relationships between their structure and insulation performance. Here, we report a rapid 10-minute gelation process under ambient temperature and pressure conditions to enable scalable manufacturing of tunable SiO₂ hollow spheres. …