Characterisation of solidification using combined confocal scanning laser microscopy with infrared thermography

Abstract

Confocal scanning laser microscopy is a growing technique as it offers the unique capability to observe (amongst other things) the solidification of high melting point materials such as steels. Here this technique has been expanded to incorporate an infrared thermographer to gain bulk information about solidification of both pure iron and a low carbon steel. This technique shows a clear indication of the onset and competition of solidification at rates up to 10 °C/s and as such becomes more applicable to the rates expected during steel casting compared to conventional calorimetry.Highlights  An upgrade of the CSLM has been proposed that incorporates thermography. Solidification has been successfully monitored using this technique  Comparisons has been made to conventional DSC techniques. ACCEPTED MANUSCRIPT A C C E P T E D M A N U S C R I P T Characterisation of solidification using combined Confocal Scanning Laser Microscopy withInfrared Thermography. ABSTRACTConfocal scanning laser microscopy is a growing technique as it offers the unique capability to observe (amongst other things) the solidification of high melting point materials such as steels. Here this technique has been expanded to incorporate an infrared thermographer to gain bulk information about solidification of both pure iron and a low carbon steel. This technique shows a clear indication of the onset and competition of solidification at rates up to 10 °C/s and as such becomes more applicable to the rates expected during steel casting compared to conventional calorimetry.

Characterization and Control of Secondary Phase Precipitation of Nb–V–Ti Microalloyed Steel during Continuous Casting Process

“…3(a)). As is found by Slater et al 23) and other scholars 12,24) , the dark particles are the direct signs of the carbonitrides. Segregation of solute atoms usually occurs at the austenite grain boundary, which accelerates the precipitation of the carbonitrides and dark particles.…”

Characterisation of the Solidification of a Molten Steel Surface Using Infrared Thermography

“…As the samples' surfaces changed emissivity, both during solidification and in the presence of a surface product, the stated temperatures in this paper refer to this calibrated point, and was, hence, why the distance away from the sample was limited to 500 µm. This method has shown very good agreement previously, where the impact of any thermal lag was shown to be negligible using differential calorimetry [19,20]. Therefore, the readings taken from the surface act to provide information on when events occur, rather than providing a direct temperature reading itself.…”

“…In more recent years its usage for steel processing, particularly in relation to oxides and slags, has gained momentum [17,18]. The work reported in this paper applied the technique, developed by Slater et al [19], of using combined infrared thermography with CSLM. The CSLM used was a Yonekura VL2000DX-SVF17SP (Yonekura, Yokohama, Japan) with a He-Ne laser as the imaging source.…”