TY - JOUR
T1 - Acoustic emission energy transfer rate
T2 - A method for monitoring abrasive waterjet milling
AU - Rabani, Amir
AU - Marinescu, Iulian
AU - Axinte, Dragos
N1 - Funding Information:
The authors would like to acknowledge the funding support of EU FP7-NMP4 (Grant no. 229155 ) for the works presented as a part of the ConforM-Jet project. We also would like to acknowledge all the partners involved in the ConforM-Jet consortium, especially Royal Institute of Technology (KTH), Fundacion Tekniker (Tekniker) for their support on this work.
PY - 2012/10
Y1 - 2012/10
N2 - Abrasive waterjet (AWJ) milling is an enabling technology for generating complex geometries; however, the lack of methods for online monitoring of jet penetration (i.e. area of abraded footprint) makes difficult to control the quality of the process. By introducing a new concept, Transfer Rate of Energy that links the input jet energy, area of abraded footprint and jet feed velocity and exploiting its property to remain constant for particular set of pump pressure and abrasive mass flow, the paper presents a method to control the jet penetration on AWJ milling. The input jet energy that produces the part erosion is monitored using an acoustic emission sensor mounted on the target workpiece surface, while the jet feed velocity is acquired online from the machine axis encoders. With the pre-evaluation of TRE as specific response of the target material (i.e. Ti6Al4V) to the AWJ milling set of parameters, the area of abraded jet footprint can be calculated on line. To make the method more powerful the input jet energy has been related to the process operating parameters (pump pressure, abrasive mass flow) while their constant values during AWJ milling process have been monitored via a pressure gauge and second acoustic emission sensor mounted on the focussing tube. The strength of the proposed monitoring method relies on the fact that via TRE it is possible to know the quantity of adjustments of the jet feed velocity to enable keeping constant the jet penetration in case of any process disturbances occur. This monitoring methodology has been demonstrated over a wide range of process parameters and it opens avenues for closed-loop control strategies of AWJ milling so that complex features can be generated with minimum human intervention.
AB - Abrasive waterjet (AWJ) milling is an enabling technology for generating complex geometries; however, the lack of methods for online monitoring of jet penetration (i.e. area of abraded footprint) makes difficult to control the quality of the process. By introducing a new concept, Transfer Rate of Energy that links the input jet energy, area of abraded footprint and jet feed velocity and exploiting its property to remain constant for particular set of pump pressure and abrasive mass flow, the paper presents a method to control the jet penetration on AWJ milling. The input jet energy that produces the part erosion is monitored using an acoustic emission sensor mounted on the target workpiece surface, while the jet feed velocity is acquired online from the machine axis encoders. With the pre-evaluation of TRE as specific response of the target material (i.e. Ti6Al4V) to the AWJ milling set of parameters, the area of abraded jet footprint can be calculated on line. To make the method more powerful the input jet energy has been related to the process operating parameters (pump pressure, abrasive mass flow) while their constant values during AWJ milling process have been monitored via a pressure gauge and second acoustic emission sensor mounted on the focussing tube. The strength of the proposed monitoring method relies on the fact that via TRE it is possible to know the quantity of adjustments of the jet feed velocity to enable keeping constant the jet penetration in case of any process disturbances occur. This monitoring methodology has been demonstrated over a wide range of process parameters and it opens avenues for closed-loop control strategies of AWJ milling so that complex features can be generated with minimum human intervention.
KW - Acoustic emission
KW - Process monitoring
KW - Transfer rate of energy
KW - Waterjet milling
UR - http://www.scopus.com/inward/record.url?scp=84862983477&partnerID=8YFLogxK
U2 - 10.1016/j.ijmachtools.2012.05.012
DO - 10.1016/j.ijmachtools.2012.05.012
M3 - Article
AN - SCOPUS:84862983477
SN - 0890-6955
VL - 61
SP - 80
EP - 89
JO - International Journal of Machine Tools and Manufacture
JF - International Journal of Machine Tools and Manufacture
ER -