TITLE:
Modeling and Simulation of Laser Assisted Turning of Hard Steels
AUTHORS:
Omar Abdulghani, Mohamed Sobih, Amro Youssef, Abdel-Monem El-Batahgy
KEYWORDS:
Laser Assisted Turning; Hard Steels; Three-Dimensional Modeling; User-Defined Function; Temperature Distribution
JOURNAL NAME:
Modeling and Numerical Simulation of Material Science,
Vol.3 No.4,
October
10,
2013
ABSTRACT: This research work is focused on simulation of laser assisted
turning as a new solution for machining of hard steels. A transient,
three-dimensional model was developed to predict the temperature distribution
of a rotated cylindrical steel workpiece subjected to a localized heating using
a moving Gaussian laser beam. In this regard, a User-Defined Function
was created to overcome the problem of a moving Gaussian heat source’ definition. This User-Defined Function was compiled into a finite volume
software package (Fluent), where three-dimensional single precision
solver was used for analysis. Based on this model, simulation of the surface
temperature of 32 mm diameter workpiece of AISI51 50H steel was
performed as a function of time at a specific distance behind the laser beam
spot, which is corresponding to 30° angle from the laser beam. The
simulation results were compared with other published data of the same steel
type where a close agreement was obtained. The verified model was used for
simulation of laser assisted turning of 20 mm diameter workpiece of AISI D2 tool steel. The cutting depth, behind the laser
beam, was set at a distance corresponding to 60° angle from the
laser beam for having sufficient access for handling both laser head and
cutting tool. This cutting depth was studied as a function of different lasers and
machining parameters. The results indicated that the optimum parameters for
successful laser-assisted turning process of the concerned steels are 800 W laser
power, 5 mm laser beam spot diameter, 20 sec
preheating time, 0.8 mm/sec laser scanning speed, 300 rpm
rotational speed and 0.8 mm/sec feed rate.
These parameters ensure easy/successful cutting of 1 mm depth in one pass
without deteriorating the properties of the remaining bulk material. It can be
deduced that the developed model might provide a useful tool for online process
control of different steel types regardless of their physical properties and
geometries.