The analysis of theavailability of AM equipment indicated that only 5% of the respondents specified that their institutions in south-westernNigeria possessed inkjet/3D printing AM equipment. It was further deduced that the highest level of awareness of 50% was for inkjet/3D printing, amongst other forms of AM/RP technology in the south-western states in Nigeria. The analysis indicated thatthere was 40% awareness of AM/RP technology in the south-western Nigeria, whereas 60% of the respondents had notpreviously heard of the technologies. In asurvey, copies of a questionnaire were administered to sixty (60) engineering personnel in research/tertiary institutions inthe south-western states in Nigeria and forty (40) useful responses were obtained and analyzed. In this paper, the level of awareness of AM/RP technology in south-western Nigeria was investigated and presented. The typical powder laser track demonstrated higher hardness (245 HV0.3) compared with the corresponding wire laser track (224 HV0.3).
However, finer dendritic microstructure and higher number density of inter-dendritic precipitates were observed in a typical powder laser track compared with the corresponding wire laser track. The tracks comprise continuous Ï’-matrix and secondary compounds (rich in Nb and Mb). Due to the higher laser beam infiltration and a larger depth of substrate penetration, higher substrate dilution was observed in the powder-fed tracks.
#Coolpack evap roll crack#
At optimized parameters, laser tracks of Inconel 625 wire and powder had a strong metallurgical bond at the track–substrate interface and no crack and pore were deposited. The micro-hardness was measured using a Vickers hardness tester. The microstructure, together with the depth of substrate penetration and the degree of dilution of the deposited tracks, was examined using an optical microscope and a scanning electron microscope (equipped with an energy-dispersive spectrometer). Inconel 625 powder and wire were deposited on the AISI 304 substrate using similar processing parameters. However, a comparative study of the surface performances of laser coatings made via powder and wire feeding systems has not been performed. It has been established that laser cladding technique is useful for enhancing surface performances, hence extending the life of many components in severe corrosive-wear environments. The tensile strength of thewalls which ranges between 474 and 525 MPa depends on the wall building directions. The macrohardness of the deposited wallsis within 167–194 HV but decreased from the bottom layer to the top layer. The microstructure of the walls revealed nearly verticalcolumnar dendrites growing perpendicularly to the horizontal. The macrohardness at different stages of the built wallswas determined using Vickers hardness tester, while the ultimate tensile strength of the walls wasinvestigated according to ASTM E8M-13 standard. The microstructures of the deposited tracks were examined using opticalmicroscopy and scanning electron microscopy. In this study, singletracks and multiple tracks (walls) of AISI 308LSi on AISI 304 substrate were laser deposited using lateralwire feeding system.
The process quality determines the end properties ofthe components hence, their lifetime performances in the service environments. Laser metal deposition using wire feeding system is increasingly becoming known as a process formaking engineering components from the scratch.
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