Experimental study on chip formation and surface quality in milling of TiB₂/Al alloy composites

ABSTRACT

The in-situ TiB₂/Al alloy composites are widely used in the aerospace industry due to excellent properties. Although TiB₂/Al alloy composites have been investigated with regard to tool wear, surface defects and cutting force, chip formation is not widely covered but is crucial to understand the machinability. Therefore, milling experiments were conducted to research chip formation, evolution from continuous chips to serrated chips, and machined surface quality. The results show that the chip morphology presented two main forms: continuous chips and serrated chips. The shear angles of the chip tend to be 45° as feed per tooth increases. Compared with TiB₂/7075 composites, the chip surfaces of TiB₂/2024 composites are more rugged and prone to crack. Some cracks of chips propagate from the bottom to the inside of chips in milling of TiB₂/2024 composite, but no similar phenomena appear at the chip surfaces in milling of TiB₂/7075 composite. Furthermore, TiB₂/Al alloy composites possess better-machined surface quality. Serrated chips deterioration machined surface quality due to the tool vibration.

KEYWORDS:

• TiB₂
• Al
• composites
• chip
• formation
• continuous
• serrated
• milling
• surface

Additional information

Funding

This work was supported by Start-Up Plan for New Young Researchers of Shanghai Jiao Tong University [19X100040014] and Fund of National Natural Science Foundation of China [51975368].