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Effect of nano-particulate sol–gel coatings on the oxidation resistance of high-strength steel alloys during the press-hardening process / M. Yekehtaz in Materials and corrosion, Vol. 63 N° 10 (Octobre 2012) 

Public ISBD [article]  in Materials and corrosion > Vol. 63 N° 10 (Octobre 2012) . - pp. 940–947 Titre : Effect of nano-particulate sol–gel coatings on the oxidation resistance of high-strength steel alloys during the press-hardening process Type de document : texte imprimé Auteurs : M. Yekehtaz, Auteur ; C. Klesen, Auteur ; S. Benfer, Auteur Année de publication : 2013 Article en page(s) : pp. 940–947 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : High-strength  steel  alloys;  nanoparticle;  oxidation  protection;  press  hardening;  sol–gel  coatings Résumé : The need for lighter constructional materials in automotive industries has increased the use of high-strength steel alloys. To enhance passenger's safety press hardening may be applied to steel parts. However, as the steel parts are heated up to 950 °C during this process they have to be protected by some kind of coating against the intense oxide formation usually taking place. As the coating systems used so far all have certain disadvantages in this work the ability of nano-particulate thin coatings obtained by the sol–gel process to improve the oxidation resistance of 22MnB5 steel is investigated. The coatings obtained from three sols containing lithium aluminum silicate and potassium aluminum silicate showed the best performance against oxidation. The structural properties of the coating materials were characterized using different methods like XRD and differential thermal analysis. Comparison of the oxidation rate constants proved the ability of the coatings to protect against oxidation at temperatures up to 800 °C. Press-hardening experiments in combination with investigations on the thermal shock resistance of the coated samples also showed the ability of the coatings to stay intact during press hardening with only slight spalling of the coatings in the bending areas. The absence of any secondary intermetallic phases and layer residues during laser beam welding experiments on coated samples proves the suitability of the nano-particulate coatings for further industrial processing. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201206729/abstract [article] Effect of nano-particulate sol–gel coatings on the oxidation resistance of high-strength steel alloys during the press-hardening process [texte imprimé] / M. Yekehtaz, Auteur ; C. Klesen, Auteur ; S. Benfer, Auteur . - 2013 . - pp. 940–947. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 63 N° 10 (Octobre 2012) . - pp. 940–947 Mots-clés : High-strength  steel  alloys;  nanoparticle;  oxidation  protection;  press  hardening;  sol–gel  coatings Résumé : The need for lighter constructional materials in automotive industries has increased the use of high-strength steel alloys. To enhance passenger's safety press hardening may be applied to steel parts. However, as the steel parts are heated up to 950 °C during this process they have to be protected by some kind of coating against the intense oxide formation usually taking place. As the coating systems used so far all have certain disadvantages in this work the ability of nano-particulate thin coatings obtained by the sol–gel process to improve the oxidation resistance of 22MnB5 steel is investigated. The coatings obtained from three sols containing lithium aluminum silicate and potassium aluminum silicate showed the best performance against oxidation. The structural properties of the coating materials were characterized using different methods like XRD and differential thermal analysis. Comparison of the oxidation rate constants proved the ability of the coatings to protect against oxidation at temperatures up to 800 °C. Press-hardening experiments in combination with investigations on the thermal shock resistance of the coated samples also showed the ability of the coatings to stay intact during press hardening with only slight spalling of the coatings in the bending areas. The absence of any secondary intermetallic phases and layer residues during laser beam welding experiments on coated samples proves the suitability of the nano-particulate coatings for further industrial processing. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201206729/abstract