Material Flow Behavior and Microstructure Evolution During Direct Hot‐Press Bonding of Ti/Mg Laminates with Interlocking Structure

Abstract

With widespread applications of electronic devices, the injuries by the complex electromagnetic environment to the electronic device industry and human health are of extensive concern, and this also promotes the exploitation of electromagneticshielding and absorbing materials. In recent years, a kind of new composite material based on the carbon framework and oxide nanoparticles exhibits excellence in the aspect of electromagnetic absorbing. [1][2][3][4] However, its formability and mechanical properties need improvement. For comparison, magnesium alloy, as a type of excellent electromagnetic-shielding material, is characterized by low density and good mechanical properties; thus, it has great application prospects in the electronic device industry. [5] However, its practical application is limited by poor corrosion resistance. [6] It is an effective method to improve the practical performance of magnesium alloys by cladding anticorrosion metals such as steel, [7] aluminum, [8] and titanium [9] to form magnesium-based laminates. Among them, Ti/ Mg laminates, which possesses lower density compared with steel/Mg laminates and higher strength than Al/Mg laminates, have great potential to be utilized in the aerospace industry.At present, the preparation methods of Ti/Mg laminates mainly include explosive welding, [10] rolling, [11] and hot pressing. [12] Explosive welding can achieve metallurgical bonding of the interface in a short time under high pressure and high temperature. However, product quality and operation safety restrict the mass application of this method. Rolling is more stable compared with explosive welding. However, large reduction is usually required to achieve reliable bonding for Ti/Mg laminates. Based on the difference between the deformation ability of titanium and magnesium, the shape and dimension of as-rolled laminates are hard to guarantee; in addition, some defects like edge cracks are easy to form in magnesium in the process of rolling. Hot pressing is widely perceived as a stable and safe way with a simple process and low cost. [13] The existing hot-pressing process can be divided into two types including hot-press diffusing and direct hot pressing. Hot-press diffusing is characterized by reliable bonding, which is achieved by elements diffusion activated thermally with the assistance of limited pressure. [14] However, this process may last for hours, which severely restricts the efficiency of this method. Direct hot pressing, by comparison, is much more efficient due to its simplified process. Interfacial bonding is achieved by pressing with large load in the condition of atmosphere. [15] However, that also increases the problem of bonding reliability, especially for immiscible metal couple like Ti/Mg. Thus, how to prepare high-performance Ti/Mg laminates with efficiency has become the bottleneck problem, restricting its mass industrial application, which urgently has to be investigated.For Ti/Mg laminates, it is hard to acquire reliable metallurgical bonding between titanium and magnesi...

Strengthening Mechanisms of Ti–Mg Composite for Biomaterials: A Review

“…However, this process can last for several hours, severely limiting the efficiency of the method. [42,43] In contrast, direct hot pressing is much more efficient because it simplifies the process. The interfacial bonding is achieved with large load pressurization under atmospheric conditions.…”