Boiling Enhanced Lidded Server Packages for Two-Phase Immersion Cooling Using 3D Metal Printing and Metal Injection Molding Technologies

In order to meet increasing performance demand from high-performance computing (HPC) and edge computing, thermal design power (TDP) of CPU and GPU needs to increase. This creates thermal challenge to corresponding electronic packages with respect to heat dissipation. In order to address this challenge, two-phase immersion cooling is gaining attention as its primary mode of heat of removal is via liquid-to-vapor phase change, which can occur at relatively low and constant temperatures. In this paper, integrated heat spreader (IHS) with boiling enhancement features is proposed. 3D metal printing and metal injection molding (MIM) are the two approaches used to manufacture the new IHS. The resultant IHS with enhancement features are used to build test vehicles (TV) by following standard electronic package assembly process. Experimental results demonstrated that boiling enhanced TVs improved two-phase immersion cooling capability by over 50% as compared to baseline TV without boiling enhanced features.

Features of Heat Treatment the Ti-6Al-4V GTD Blades Manufactured by DLD Additive Technology

Additive manufacturing of titanium alloys is one of the fastest growing areas of 3D metal printing. The use of AM methods for parts production in the aviation industry is especially promising. During the deposition of products with differently sized cross-sections, the thermal history changes, which leads to non-uniformity of the structure and properties. Such heterogeneity can lead to failure of the product during operation. The structure of deposited parts, depending on the thermal cycle, may consist of α’, α + α’ + β’, and α + β in different ratios. This problem can be solved by using heat treatment (HT). This paper presents research aimed towards the determination of optimal heat treatment parameters that allows the reception of the uniform formation of properties in the after-treatment state, regardless of the initial structure and properties, using the example of a deposited Ti-6Al-4V gas turbine blade.

Novel Approaches to the Design of an Ultra-Fast Magnetorheological Valve for Semi-Active Control

This article presents a list of suitable techniques and materials leading to the design of an ultra-fast magnetorheological (MR) valve. Two approaches for achieving the short response time are proposed: (a) by means of material, and (b) by means of the shape. Within the shape approach, the revolutionary technique of 3D metal printing using a selective laser melting (SLM) method was tested. The suitability of the materials and techniques is addressed based on the length of the response time, which is determined by the FEM. The simulation results determine the response time of the magnetic flux density on the step signal of the current. Subsequently, the response time is verified by the measurement of the simple magnetorheological valve. The following materials were tested: martensitic stainless steel AISI 420A (X20Cr13), cutting steel 11SMn30, pure iron for SLM, Sintex SMC STX prototyping material, ferrite N87, and Vacoflux 50. A special technique involving grooves was used for preventing eddy currents on materials with a high electrical conductivity. The simulation and experimental results indicate that a response time shorter than 2.5 ms can be achieved using materials such as Sintex SMC prototyping, ferrite N87, and grooved variants of metal pistons.