Friction Surfacing From Radial Surface of A6063 Aluminum Alloy Consumable Tool Onto A36 Carbon Steel

Friction surfacing process is an advanced technique to create solid-state deposition of wide range of materials onto a similar or dissimilar material substrate.  This paper describes the study of a novel method to deposit material onto a substrate by friction surfacing.  In the friction surfacing technique, the heat is generated entirely by friction.  This metallic deposition technique consists of a rotating consumable tool that rubs against the surface of the substrate, and due to the frictional heat and forging generated between the tool and substrate, material is deposited onto the substrate.  The material transferred from the consumable tool to the substrate occurs from the side of the tool, while in the conventional friction surfacing method, the material transfer happens from the end of the tool.  In this investigation, the single and double-pass deposition of A6063 aluminum alloy onto an A36 carbon steel substrate was successfully carried out.  In order to study the influence of the process parameters on the friction depositions, the substrate was divided into three sections, while the applying forces were varied in each section.  Process parameters such as tool rotational speeds of 2300 and 3000 rpm, table traverse speeds of 76.2 and 114.3 mm/min, and normal forces of 50, 100, and 150 N were experimented.

A customized JET JMD-18 milling machine was used to carry out the experiments.  The manual feed handle of the milling machine’s table was removed, and the table was equipped with a servo power table feed to provide a uniform longitudinal table movement and increase the accuracy of the experiments.  Force was measured and recorded during the friction deposition process using a dynamometer and LabVIEW programming. 

The influence of process parameters on the material deposition was characterized by means of roughness tester, optical microscope, and visual evaluation.  The results of the study reveal that this novel method is capable to create an ultra-thin and smooth metallic deposition with excellent coverage.  The material consumption during the single and double-pass deposition was evaluated, and the coating cross-section was assessed using the optical microscope.  The experimental results show a high quality and great coverage for both single and double-pass friction depositions; however, the deposition created in the two-pass coating process has a slightly better coverage.  Moreover, the experimental results indicate that the first deposition layer of A6063 had a smoother surface roughness than the substrate.  Further adding the second deposition layer resulted in even smoother surface roughness.