Drilling Process in γ-TiAl Intermetallic Alloys.

Area of Science:

• Materials Science
• Manufacturing Engineering

Background:

• Gamma titanium aluminides (γ-TiAl) offer superior high-temperature performance, making them suitable replacements for nickel-based superalloys in aeroengines.
• Machining γ-TiAl is challenging due to its material properties, necessitating careful control of cutting parameters to maintain component integrity.

Purpose of the Study:

• To develop and validate a mechanistic drilling model for predicting drilling forces (F) and torque (T) in γ-TiAl alloys.
• To provide a tool for selecting optimal drilling parameters, preventing potential damage from excessive forces and torques.

Main Methods:

• A mechanistic drilling model was developed to predict cutting forces and torque.
• The model was validated using integral hard metal end-drilling tools across three different γ-TiAl alloys.
• Experiments involved drilling three distinct hole sizes with varying feed rates and cutting speeds.

Main Results:

• The developed model accurately predicts drilling forces (F) and torque (T) for γ-TiAl alloys.
• The model aids in identifying machining parameters that avoid detrimental force and torque levels.
• Validation confirmed the model's effectiveness across different alloys and hole sizes.

Conclusions:

• The mechanistic drilling model is a valuable tool for optimizing machining processes for γ-TiAl.
• Implementing this model enhances the ability to machine γ-TiAl components with guaranteed quality.
• This research contributes to the wider adoption of γ-TiAl in demanding aeroengine applications.