Laser Machining of AISI 304: An Experimental Study …
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that width of heat-affected zone was affected importantly due to gas pressure by the
generation of adhering dross height on the lower part of cut material. Ahn et al. [12]
observed the higher amount of dross formed at the lower part because of excessive
material melting. Muhammad et al. [13] experimented on fiber laser machining for
stainless steel circular tube and its effects by allowing water to flow through tubes
for dross height formations. Yan et al. [14] have investigated striation and dross-free
cutting on alumina sheet using fiber laser machining. Baxter et al. [15] developed
oxygen gas system for the introduction of gas throughout the workpiece to oxidize
dross height formation during laser cutting. Oxygen gas cools the dross as well as
workpiece while at the same time oxidizes it. Teixidor et al. [16] analyzed dross
height formation for the energy balances during fiber laser machining. Jarosza et al.
[17] experimented that rise in occurrence of dross height and molten material metal
along with a rough surface on the lower part of workpiece is due to lower cutting
speed. Furthermore, occurence of burnt metal had been investigated at the lower part
of workpiece with the lowest speed. Madhukar et al. [18] found that dross height
varies with power of laser and cutting speed. Bara et al. [19] investigated the effects
on process input parameters for drilled characteristics of stainless steel on 1.5 mm
thickness sheet workpiece with fiber laser process. Rahimia et al. [20] studied on
composite material for laser-engraving performance characteristics.
From the literature review, it can be concluded that most of the researchers have
tried out efforts for the investigation of influence on input process parameters for laser
machining on responses, namely kerf top-bottom width, kerf taper angle and kerf
deviation, heat-affected zone, surface roughness, striations, dross, etc. However, very
limited researchers had investigated the experimental results of input process parameters on dross properties in laser machining of thick steel material. This experimental
study is concentrated for investigation of influence of input process parameters on
laser machining of thick AISI 304 stainless steel on dross height. This paper has been
integrated as follows: Sect. 1 describes introduction, Sect. 2 gives experimental work,
and results and discussion part is presented in Sect. 3, Sect. 4 discusses optimization
of process parameters, and finally, concluding remarks are given in Sect. 5.
2 Experimental Work
For present study, Bystronic fiber laser machine is used for conduction of experiments
available at M/s Kakade Laser, Narhe, Pune, India. It produces 1.06 µm wavelength,
and 6000 W is the highest laser output power. During performance of experiments,
128 mm was the focal length of the lens and 4 mm nozzle diameter that was maintained constant throughout. 1.5 mm was nozzle stand-off distance maintained during
the experiments. A thick AISI 304 stainless steel of 20 mm thickness plate is considered as workpiece material. The maximum chemical composition and mechanical
properties for AISI 304 material are depicted in Tables 1 and 2, respectively. For
experimentation, 17 workpiece samples of size 20 × 20 mm are cut.
539
that width of heat-affected zone was affected importantly due to gas pressure by the
generation of adhering dross height on the lower part of cut material. Ahn et al. [12]
observed the higher amount of dross formed at the lower part because of excessive
material melting. Muhammad et al. [13] experimented on fiber laser machining for
stainless steel circular tube and its effects by allowing water to flow through tubes
for dross height formations. Yan et al. [14] have investigated striation and dross-free
cutting on alumina sheet using fiber laser machining. Baxter et al. [15] developed
oxygen gas system for the introduction of gas throughout the workpiece to oxidize
dross height formation during laser cutting. Oxygen gas cools the dross as well as
workpiece while at the same time oxidizes it. Teixidor et al. [16] analyzed dross
height formation for the energy balances during fiber laser machining. Jarosza et al.
[17] experimented that rise in occurrence of dross height and molten material metal
along with a rough surface on the lower part of workpiece is due to lower cutting
speed. Furthermore, occurence of burnt metal had been investigated at the lower part
of workpiece with the lowest speed. Madhukar et al. [18] found that dross height
varies with power of laser and cutting speed. Bara et al. [19] investigated the effects
on process input parameters for drilled characteristics of stainless steel on 1.5 mm
thickness sheet workpiece with fiber laser process. Rahimia et al. [20] studied on
composite material for laser-engraving performance characteristics.
From the literature review, it can be concluded that most of the researchers have
tried out efforts for the investigation of influence on input process parameters for laser
machining on responses, namely kerf top-bottom width, kerf taper angle and kerf
deviation, heat-affected zone, surface roughness, striations, dross, etc. However, very
limited researchers had investigated the experimental results of input process parameters on dross properties in laser machining of thick steel material. This experimental
study is concentrated for investigation of influence of input process parameters on
laser machining of thick AISI 304 stainless steel on dross height. This paper has been
integrated as follows: Sect. 1 describes introduction, Sect. 2 gives experimental work,
and results and discussion part is presented in Sect. 3, Sect. 4 discusses optimization
of process parameters, and finally, concluding remarks are given in Sect. 5.
2 Experimental Work
For present study, Bystronic fiber laser machine is used for conduction of experiments
available at M/s Kakade Laser, Narhe, Pune, India. It produces 1.06 µm wavelength,
and 6000 W is the highest laser output power. During performance of experiments,
128 mm was the focal length of the lens and 4 mm nozzle diameter that was maintained constant throughout. 1.5 mm was nozzle stand-off distance maintained during
the experiments. A thick AISI 304 stainless steel of 20 mm thickness plate is considered as workpiece material. The maximum chemical composition and mechanical
properties for AISI 304 material are depicted in Tables 1 and 2, respectively. For
experimentation, 17 workpiece samples of size 20 × 20 mm are cut.