{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T23:30:43Z","timestamp":1784331043723,"version":"3.55.0"},"reference-count":79,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2021,7,31]],"date-time":"2021-07-31T00:00:00Z","timestamp":1627689600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001602","name":"Science Foundation Ireland","doi-asserted-by":"publisher","award":["16\/RC\/3872"],"award-info":[{"award-number":["16\/RC\/3872"]}],"id":[{"id":"10.13039\/501100001602","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Injection moulding is an extremely important industrial process, being one of the most commonly-used plastic formation techniques. However, the industry faces many current challenges associated with demands for greater product customisation, higher precision and, most urgently, a shift towards more sustainable materials and processing. Accurate real-time sensing of the material and part properties during processing is key to achieving rapid process optimisation and set-up, reducing down-times, and reducing waste material and energy in the production of defective products. While most commercial processes rely on point measurements of pressure and temperature, ultrasound transducers represent a non-invasive and non-destructive source of rich information on the mould, the cavity and the polymer melt, and its morphology, which affect critical quality parameters such as shrinkage and warpage. In this paper the relationship between polymer properties and the propagation of ultrasonic waves is described and the application of ultrasound measurements in injection moulding is evaluated. The principles and operation of both conventional and high temperature ultrasound transducers (HTUTs) are reviewed together with their impact on improving the efficiency of the injection moulding process. The benefits and challenges associated with the recent development of sol-gel methods for HTUT fabrication are described together with a synopsis of further research and development needed to ensure a greater industrial uptake of ultrasonic sensing in injection moulding.<\/jats:p>","DOI":"10.3390\/s21155193","type":"journal-article","created":{"date-parts":[[2021,8,1]],"date-time":"2021-08-01T21:44:32Z","timestamp":1627854272000},"page":"5193","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Ultrasound Sensors for Process Monitoring in Injection Moulding"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2185-7284","authenticated-orcid":false,"given":"Mandana","family":"Kariminejad","sequence":"first","affiliation":[{"name":"Centre for Precision Engineering, Materials and Manufacturing (PEM Centre), Institute of Technology Sligo, Ash Lane, F91 YW50 Sligo, Ireland"},{"name":"Centre for Mathematical Modelling and Intelligent Systems for Health and Environment (MISHE), Institute of Technology Sligo, Ash Lane, F91 YW50 Sligo, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4250-6056","authenticated-orcid":false,"given":"David","family":"Tormey","sequence":"additional","affiliation":[{"name":"Centre for Precision Engineering, Materials and Manufacturing (PEM Centre), Institute of Technology Sligo, Ash Lane, F91 YW50 Sligo, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saif","family":"Huq","sequence":"additional","affiliation":[{"name":"School of Computing and Digital Media, London Metropolitan University, 166-220 Holloway Rd, London N7 8DB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jim","family":"Morrison","sequence":"additional","affiliation":[{"name":"Department of Electronics and Mechanical Engineering, Letterkenny Institute of Technology, Port Rd, Gortlee, Letterkenny, F92 FC93 Donegal, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1434-1215","authenticated-orcid":false,"given":"Marion","family":"McAfee","sequence":"additional","affiliation":[{"name":"Centre for Precision Engineering, Materials and Manufacturing (PEM Centre), Institute of Technology Sligo, Ash Lane, F91 YW50 Sligo, Ireland"},{"name":"Centre for Mathematical Modelling and Intelligent Systems for Health and Environment (MISHE), Institute of Technology Sligo, Ash Lane, F91 YW50 Sligo, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kazmer, D.O. 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