Evidence map›Paper›PMID 41142360›Full record

ArticlePhotoacoustics2025

Artificial intelligence-assisted laser ultrasound method for the estimation of porosity in hairpin weld seams.

Markus Saurer, Guenther Paltauf, Oliver Spitzer, Tobias Reitmayr, Gordana Djuras, Birgit Kornberger, Ulrike Kleb, Robert Nuster

Abstract read
In one paragraph

Article in Photoacoustics, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Markus SaurerDepartment of Physics, University of Graz, Universitaetsplatz 5, Graz, 8010, Austria.
Guenther PaltaufDepartment of Physics, University of Graz, Universitaetsplatz 5, Graz, 8010, Austria.
Oliver SpitzerMiba Automation Systems, Aurachkirchen 45, Aurachkirchen, 4812, Austria.
Tobias ReitmayrMiba Automation Systems, Aurachkirchen 45, Aurachkirchen, 4812, Austria.
Gordana DjurasPOLICIES - Institute for Economic, Social and Innovation Research, JOANNEUM RESEARCH, Leonhardstraße 59, Graz, 8010, Austria.
Birgit KornbergerPOLICIES - Institute for Economic, Social and Innovation Research, JOANNEUM RESEARCH, Leonhardstraße 59, Graz, 8010, Austria.
Ulrike KlebPOLICIES - Institute for Economic, Social and Innovation Research, JOANNEUM RESEARCH, Leonhardstraße 59, Graz, 8010, Austria.
Robert NusterDepartment of Physics, University of Graz, Universitaetsplatz 5, Graz, 8010, Austria.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Hairpin technology is being used as a replacement for the traditional winding stator in electric motors. In hairpin stator manufacturing, copper rods are used to achieve a higher slot fill factor. These rods are joined together in pairs through laser welding, forming a closed circuit. However, this welding process is prone to air inclusions in the welds, which can negatively impact the efficiency and durability of the motor. The present study aims to estimate the total volume of these air inclusions using laser ultrasonic measurements. Laser ultrasound is a fast, non-contact, non-destructive method that can cope with the limited sample accessibility, making it ideal for inline testing of these weld seams. To evaluate the effectiveness of laser ultrasound, a stator was intentionally manipulated prior to laser welding to favor the formation of air inclusions. The porosity of the weld seams was determined through computed tomography images. It was demonstrated that due to the complex geometry of the hairpin welds, leading to a complex ultrasound wave field, standard methods to estimate the porosity from laser ultrasound B-scans are difficult to apply. As an alternative approach, an algorithm that is based on artificial intelligence was utilized for the purpose of estimating the air inclusion volume in the welds from laser ultrasonic measurements. The outcomes demonstrated a median correlation of 0.6 between this estimate and the pore volume obtained from the computed tomography data, despite the utilization of only 48 samples. Moreover, these results were evaluated against a model where the labels were randomly mixed, and highly informative regions regarding pore volume were identified in the B-scans, which have the potential to accelerate the process of acquiring data.

Indexed as

Artificial intelligenceHairpin statorLaser ultrasoundWeld seam inspection

Identifiers

PMID41142360
PMCPMC12547966

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.