CNC Machining Process for Titanium Alloy Materials

　　Titanium alloys, valued for their high strength-to-weight ratio and corrosion resistance, present unique challenges in CNC machining due to their low thermal conductivity and high chemical reactivity. The machining process begins with tool material selection. Cemented carbide tools with coated inserts (such as TiAlN or AlTiN) are ideal, as they withstand high temperatures (up to 800°C) generated during cutting. Uncoated carbide may rapidly wear due to titanium’s tendency to weld to the tool surface.

　　Cutting parameters are carefully calibrated. Spindle speeds are moderate (500–3,000 RPM) to avoid excessive heat buildup, as titanium’s low thermal conductivity traps heat in the cutting zone, leading to tool degradation. Feed rates are kept low (0.05–0.2 mm/rev) to reduce cutting forces and minimize work hardening. Depth of cut is typically 0.5–3 mm, balancing material removal and tool life.

　　Cooling and lubrication are critical. High-pressure coolant systems (30–100 bar) direct coolant to the cutting edge, dissipating heat and flushing chips. Oil-based coolants with extreme pressure additives prevent friction and welding. Workholding requires rigid fixtures to counteract vibration, as titanium’s high strength can cause tool chatter. Using sharp tools and avoiding interrupted cuts (where possible) reduces tool stress. Post-machining, parts may undergo stress relief heat treatment to eliminate residual stresses caused by machining, ensuring dimensional stability.