•  
  •  
 

Corresponding Author

Ahmed Elkaseer

Authors ORCID

https://orcid.org/0000-0002-2500-3617

Document Type

Original Study

Subject Areas

Manufacturing Engineering

Keywords

Micro drilling; stainless steel AISI304; MEBH; roundness; RMSE; ANOVA; statistical analysis.

Abstract

Austenitic stainless steel AISI304, known for its outstanding mechanical, physical properties, and biocompatibility, is a preferred material for diverse applications. Its hard-to-machine nature presents challenges such as rapid tool wear and poor thermal conductivity, affecting machining quality. This study takes a deep look at the micro drilling of such challenging gap of AISI 304 with 0.8 mm tungsten carbide micro drills, focusing on how key process parameters; linear cutting speed, feed per tooth, and cutting length affect maximum exit burr height and roundness through interaction effects among these factors to identify better drilling conditions with better responses. Utilizing a factorial design, parameters were tested across five levels of cutting speed and feed per tooth and two levels of cutting length to assess their impacts. Maximum exit burr height was measured under 10x magnification with an optical microscope, while roundness was analyzed using a MATLAB script. Multiple polynomial regression models were developed using a MATLAB script for predicting output responses with R squared = 0.901, 0.914 for both burr height and roundness, respectively. Also, the root mean square error (RMSE) for burr height was calculated to be 9.4127, while the RMSE for roundness was 0.000883 reflecting the high accuracy of the developed regression models in predicting the output responses. ANOVA results reveal that linear cutting speed (p-value = 6.0387 × 10^−5) was the most critical factor influencing maximum exit burr height. In contrast, feed per tooth significantly affects roundness (p-value = 1.2456 × 10^−5) more than other factors. An excessive cutting speed led to increased burr height, while an in crease in feed per tooth and cutting length mitigated this effect. Conversely, an increase in feed per tooth, cutting speed, and a relatively slight rise in cutting length was associated with improved roundness, The findings highlight a trade-off between the influential process parameters on burr height and roundness, emphasizing the need for optimized machining practices for AISI304.

Download

Share

COinS