Effect of 0.20% Beryllium (Be)-Added CuAl10Ni5Fe4 Alloy on Tribological Behavior and Microstructural Properties After Post-Casting Heat Treatment and Forging Process

This study explored how post-casting heat treatment and forging affected the tribological and microstructural characteristics of 0.20% beryllium (Be)-added CuAl₁₀Ni₅Fe₄ alloys. The heat-treated CuAl₁₀Ni₅Fe₄ microstructure exhibits a copper-rich α (alpha)-solid-solution phase, a martensitic β (beta)-phase, and diverse intermetallic κ (kappa)-phases, such as leaf-shaped κ_I, thin κ_III, and black globs. Adding 0.20% beryllium to CuAl₁₀Ni₅Fe₄ alloys enhanced the dendritic arm thickness, needle-like shape, and κ-phase quantities. Significant κ_IV- and κ_II-phase precipitation was observed in the tempered β-phase. Beryllium improves the aluminum matrix's microstructure. Forging greatly reduced the microstructural thickness of CuAl₁₀Ni₅Fe₄ and CuAl₁₀Ni₅Fe₄-0.20% Be alloys. The forging process also developed new κ_IV-phases. Wear resistance and hardness improved with beryllium. The CuAl₁₀Ni₅Fe₄-0.20% Be alloy had the highest hardness values (235.29 and 255.08 HB) after solution treatment (ST) and tempering (T) after casting and forging (F). The CuAl₁₀Ni₅Fe₄-0.20% alloy with Be added had the best wear after solution treatment, tempering, and forging. The CuAl₁₀Ni₅Fe₄-0.20% Be alloy demonstrated a 0.00272 g weight loss, a 1.36 × 10^-8 g/N*m wear rate, and a 0.059 friction coefficient at 10,000 m after forging (F).