Session: 03-03-05: Annual Congress-Wide Symposium on Additive Manufacturing V

Paper Number: 168178

Plasma Transferred Arc Additive Manufacturing of High-Chromium White Iron: Parameter Optimization and Interpass Temperature Control for Repair Applications 

High-chromium white iron (HCWI) is a highly abrasion resistant material known for its exceptional hardness and wear resistance. This alloy typically contains 23–28% chromium, promoting the formation of hard M7​C3​ carbides embedded within a martensitic or austenitic matrix and providing superior resistance to erosion, impact, and corrosion. These characteristics make HCWI an ideal material for demanding applications in industries such as mining, cement, and dredging, where components experience extreme wear. Common applications include crusher liners, slurry pump parts, and chute liners. In these components, routine maintenance is essential to address equipment damage and malfunctions. Additive manufacturing (AM) presents a promising solution for a fast, cost-effective component repairs, reducing downtime and overall equipment costs.

Plasma transferred arc additive manufacturing (PTA-AM), a subset of directed energy deposition (DED), utilizes a focused heat source to melt and deposit feedstock material layer by layer. Initially developed for surface modifications, PTA-AM has evolved into an effective manufacturing and repair technique, particularly for wear-resistant components used in mining, oil & gas, and heavy machinery industries. This process offers precise control over dilution, microstructure, and material composition, making it particularly suitable for producing high-hardness, corrosion-resistant deposits.

Due to HCWI's high brittleness, research on its AM applications remains limited, and no prior work has been reported on using PTA-AM for its repair or fabrication. This study focuses on optimizing the processing conditions and characterizing PTA-AM’d HCWI (ASTM A532 Class III Type A). Depositions of HCWI powder are performed on industrial HCWI substrates to replicate real-world conditions. A central composite design of experiments (DOE) is employed to determine the optimal operating parameters for successful deposition. Initial experiments helped in identifying suitable processing conditions but also revealed challenges associated with residual stress and cracking in the printed beads, primarily due to HCWI's inherent brittleness. To mitigate these issues, preheating and interpass temperature control are introduced as key independent variables in subsequent experiments. The substrate is heated and maintained at temperatures between 400°C and 800°C, with thermal monitoring performed using Optris IR cameras. The deposited material is then analyzed for microstructure, phase composition, microhardness, and abrasive wear resistance.

The objective of this study is to establish correlations between preheating/interpass temperature and material properties, providing insights into the microstructural evolution and mechanical behavior of PTA-AM HCWI. Understanding these relationships will help in optimizing processing conditions to enhance wear resistance and mechanical performance, ultimately improving the longevity and reliability of repaired HCWI components.

Presenting Author: Shriyash R Waghmare University of Alberta

Presenting Author Biography: Shriyash R. Waghmare is an MSc student at the University of Alberta. He completed his bachelor's degree in mechanical engineering from the Modern Education Society’s Wadia College of Engineering, Pune University. He is working on additive manufacturing, plasma transferred arc welding, and high-chrome white iron characterization. His research focuses on characterizing the microstructure, hardness, wear resistance, and other mechanical properties of high-chromium white iron, specifically in relation to the effects of various welding and additive manufacturing techniques.

Authors:

Shriyash R Waghmare University of Alberta
Shalini Singh University of Alberta
Sajid Butt University of Alberta
Hani Henein University of Alberta
Kimberley Meszaros InnoTech Alberta
Ahmed Jawad Qureshi University of Alberta