Review on the Effect of Deep Cryogenic Treatment of Metallic Materials in Automotive Applications

Abstract

With the development of society, every year there are increasing demands in the automotive industry on cost savings, environmental safety, reduction of raw material consumption, performance improvement, material life cycle and recycling of components. In this review, emphasis is given on ferrous and non-ferrous alloys, which are used as components, where both groups can be treated by deep cryogenic treatment (DCT). DCT has shown to increase hardness, tensile strength and wear resistance, reduce density of defects in crystal structure, improve toughness and corrosion resistance. Though, some researchers also reported results that showed no change in material properties, or even deterioration of material properties, when subjected to DCT. This additionally points out to lack of consistency and reliability of the DCT process, which is needed for its successful incorporation in automotive applications. However, to prove with certainty the resulting outcome on the material properties and knowledge about the reasons for the variation of this effect on metallic materials, further approach and testing with different variables should be conducted in the future. This review provides a synopsis of different approaches of DCT on different materials for automotive applications in order to indicate effects on the material performance during DCT.

Revealing the Pb Whisker Growth Mechanism from Al-Alloy Surface and Morphological Dependency on Material Stress and Growth Environment

“…This process allows the application of uniform shrinkage pressure onto the material, which in turn modifies the internal stress state of the material. As shown by different investigations, DCT reduces tensile residual stresses or even changes them into a compressive type [ 41 , 42 , 43 , 44 ]. For the whisker preparation, all samples were cut, ground down to 4000 grit paper and polished with 3 μm and 1 μm diamond suspension.…”

Experimental Investigation of Dry and Cryogenic Friction Stir Welding of AA7075 Aluminium Alloy

“…Careful thermal insulation is done with help of foam (polymer in nature) in order to prevent being affected by external heat during the transfer. e nozzle is availed to point the fluid towards the friction stir welding zone [12,[14][15][16][17][18][20][21][22]]. An AWM720P1 flow sensor is availed to ensure a constant volume flow rate for liquid nitrogen at 1 bar pressure atmospheric pressure which is 1.977 litres/minute, by taking the total head loss in consideration, elevation point of the FSW setup, and having initial velocity and exit pressure to be zero.…”

“…Corresponding to enhanced surface properties, nil change to the composition and high strength of the tool profile are added factors to explore the application of cryogenics in the welding operation [12,13,15]. With a clear abundance availability of liquid helium, hydrogen, oxygen, and nitrogen, subzero liquid comprising of nitrogen is given the preference owing to the ratio of expansion and abundant supply present in the atmosphere [12,13,[16][17][18].…”

Influence of the Deep Cryogenic Treatment on AISI 52100 and AISI D3 Steel’s Corrosion Resistance

“…One of the possibilities to improve corrosion resistance of metals is by manipulating the metal surface by heat treatment [ 4 ] that tailors the material microstructure [ 5 ]. In the course of the past decade, a novel way of manipulating metallic surfaces has been developed by adding deep cryogenic treatment (DCT) as an accompanying heat treatment process [ 6 ]. During DCT, material is exposed to sub-zero temperatures (below −150 °C) for a certain period of time (usually between 24 and 48 h) in order to improve various material properties, including corrosion resistance [ 7 , 8 ].…”