Metallurgical and Materials Data

Discontinuous precipitation: challenge that Branko Djurić faced with U-Nb alloy

Karlo Raić — Wed, 31 Dec 2025 00:00:00 +0000

This brief overview outlines the discoveries of our colleague Branko Djurić, which appeared in the 1960s and still attract significant attention today. The presented results are related to isothermal transformation kinetics as well as the decomposition of the gamma phase (γ) in the uranium-niobium alloys.

It is also indicated, according to Branko Djurić, that the discontinuous precipitation (DP) of U-Nb alloys is interesting because it permits the development and expansion of the metastable γ′ phase while it occurs.

Titanium: Abundance, Properties, Recovery from Red Mud and Applications of a Strategic Engineering Material

Mile Djurdjevic, Srecko Stopic, Srecko Manasijevic — Wed, 31 Dec 2025 00:00:00 +0000

Titanium, although abundant in the Earth's crust, holds strategic value due to its exceptional strength-to-weight ratio, corrosion resistance, biocompatibility, and high-temperature performance. This paper reviews the geological distribution, historical discovery, and evolution of titanium's commercial production through the Hunter and Kroll processes. Titanium's allotropic nature enables the development of alpha, beta, and alpha-beta alloys tailored for diverse engineering applications. Key mechanical and chemical properties are analyzed, highlighting titanium's utility in aerospace, biomedical, marine, and chemical industries. Emerging applications and technologies such as additive manufacturing and powder metallurgy are explored for their potential to reduce production costs and enable advanced designs. Furthermore, innovative approaches to titanium recovery from secondary raw materials such as red mud are discussed to address production costs and improve sustainability. Finally, the paper addresses challenges in processing, cost, and sustainability that must be overcome to expand titanium's role in next-generation technologies. Unlike previous reviews that focus on isolated aspects such as alloy development or specific applications, this work uniquely integrates titanium's abundance paradox with the technological and economic barriers in primary production, explores emerging secondary recovery routes from industrial waste streams, and connects these processing challenges to current and future applications. This integrated framework provides a comprehensive perspective on how to advance titanium from an abundant but underutilized element to a more accessible engineering material.

Advances in Projected Capacitive Touch Panels: Innovations in Materials and Fabrication Techniques

Saeideh Alipoori, Milad Mehranpour — Wed, 20 Aug 2025 00:00:00 +0000

Touch panels are one of the most commonly used technologies in a wide range of applications, including mobile phones, tablets, and displays. Among the various types of touch panel sensors, projected capacitive touch panels (PCTPs) are the most popular due to their excellent optical performance, high durability, multi-touch functionality, and precise touch-point detection. A PCTP features a multi-layer structure consisting of two layers of electrode materials and an insulating adhesive layer. The patterning of touch panel conductors significantly impacts the performance, accuracy, and sensitivity of the touch panels. Indium tin oxide (ITO) is the most commonly employed transparent conductive material in touch panel technologies. However, its drawbacks, including the scarcity of indium, elevated cost, and intrinsic mechanical fragility, have been well recognized. Among the alternative materials for replacing ITO, poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) has emerged as a strong alternative because of its outstanding properties, such as high transparency, excellent conductivity, and mechanical flexibility. The traditional electrode patterning technique for PEDOT:PSS electrodes in touch panel applications is printing, which offers several advantages over conventional methods, including low cost, high accuracy, and rapid processing.

In this study, we review the recent advancements in PEDOT:PSS-based electrode patterning techniques for PCTPs, emphasizing printing technologies such as inkjet printing, screen printing, and other emerging methods. We evaluate their compatibility with PEDOT:PSS, technical challenges, performance metrics, and their role in replacing ITO. The paper also outlines future directions for the development of cost-effective, scalable, and flexible touch panel devices.

Plasma-Deposited Gold Nanoparticles as a Green Alternative to ENIG Circuit Boards

Lan Kresnik, Peter Majerič, Rebeka Rudolf — Wed, 31 Dec 2025 00:00:00 +0000

Next-generation space missions require electronics that can operate reliably under extreme radiation, thermal cycling, vacuum exposure and multi-year mission durations, while supporting increasingly demanding high-frequency communication and sensing systems. Commercial printed circuit boards (PCBs) finished with electroless nickel immersion gold (ENIG) remain widely used in aerospace, yet the Ni–P barrier layer introduces environmental, recyclability and high-frequency performance limitations that are becoming incompatible with emerging mission requirements and future visions of in-situ manufacturing. This work presents plasma-printed gold nanoparticle (AuNP) PCBs as a nickel-free, additive alternative platform designed to address these challenges. AuNPs synthesised via ultrasonic spray pyrolysis (USP) and deposited through plasma-assisted printing form gold conductive traces without chemical baths or multilayer structures. Demonstrations on alumina substrates show that the resulting microstrip transmission lines achieve insertion and return losses comparable to ENIG-finished PCBs up to 20 GHz, validating the approach for space-grade RF applications. Beyond performance parity, AuNP-based PCBs offer closed-loop recyclability and compatibility. Together, these results position plasma-printed AuNPs as a promising foundation for sustainable, high-frequency and space-ready electronics.

Nanowaste Management and Potential Nanomaterial Recycling Technologies

Rebeka Rudolf, Senka Šekularac Ivošević, Špiro Ivošević, Peter Majerič — Wed, 31 Dec 2025 00:00:00 +0000

This review article presents different types of nanotechnologies and synthesis of nanomaterials. The use of nanomaterials in different sectors is presented. The following discusses the issue of when the post-use phase of nanomaterials occurs and when they become nanowaste. This waste must be handled carefully so as not to endanger human health and the environment. In this discussion, we therefore present potential approaches that could be used in the future for recycling nanomaterials. Namely, the idea is to include nanomaterials in the circular economy, so that the way of organizing their synthesis and consumption, which is based on sharing, reuse, repair, renovation and recycling of existing nanomaterials and nanoproducts, would be as long as possible.