Influence of laser power on microstructure of laser metal deposited 17-4 ph stainless steel
- Authors: Adeyemi, A.A. , Akinlabi, Esther Titilayo , Mahamood, R.M. , Sanusi, K.O. , Pityana, S. , Tlotleng, M.
- Date: 2017
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/244692 , uj:25306 , Citation: Adeyemi, A.A. et al. 2017. Influence of laser power on microstructure of laser metal deposited 17-4 ph stainless steel.
- Description: Abstract: The influence of laser power on the microstructure of 17-4 PH stainless steel produced by laser metal deposition was investigated. Multiple-track of 17-4 stainless steel powder was deposited on 316 stainless steel substrate using laser metal deposition, an additive manufacturing process. In this research, laser power was varied between 1.0 kW and 2.6 kW with scanning speed fixed at 1.2 m/s. The powder flow rate and the gas flow rate were also kept constant at values of 5 g/min and 2 l/min respectively. The microstructure was studied under optical microscope and it revealed that the microstructure was dendritic in structure with finer and lesser δ-ferrite at low laser power while the appearance of coarse and more δ-ferrite are seen at higher laser power.
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Microstructural evolution of laser metal deposited 17-4 PH SS-tungsten composite with varying volume percent tungsten
- Authors: Adeyemi, A.A. , Akinlabi, Esther Titilayo , Mahamood, R.M.
- Date: 2018
- Subjects: Laser Metal Deposition , Laser Power , Microstructure
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/290972 , uj:31595 , Citation: Adeyemi, A.A., Akinlabi, E.T. & Mahamood, R.M. 2018. Microstructural evolution of laser metal deposited 17-4 PH SS-tungsten composite with varying volume percent tungsten.
- Description: Abstract: This study investigates the influence of quantity of tungsten powder on the microstructural evolution of 17-4 PH stainless steel-tungsten composite produced using laser metal deposition process. The 17-4 PH stainless steel and tungsten powders were deposited on 316 stainless steel substrate at laser power of 2600 W. The tungsten powder flow rate was varied between 0.5 rpm and 2.0 rpm while 17-4 PH stainless steel powder flow rate, the scanning speed, the gas flow rate and the laser spot size were fixed at 2.0 rpm, 0.5 m/s, 2.5 l/min and 2.0 mm respectively. Five (5) multiple track of 17-4 PH stainless steel and tungsten powder were deposited on 316 stainless steel of thickness 10 mm from different hopper at 50% overlapping percentage to produce 17-4 PH SS-W composite. During the microstructural study, it was observed that tungsten carbide has been precipitated in-situ and evenly dispersed in the 17-4 PH SS-W composite produced. SEM and EDS analysis also revealed the presence of BCC alpha (α) ferrite and FCC gamma (δ) ferrite with the presence of sigma (σ) phase precipitates.
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