Experimental-Numerical Study of Tensile Strength of the High-Strength Steel S690QL at Elevated Temperatures

Abstract

Ïðåäñòàâëåíû ðåçóëüòàòû ðàñ÷åòíî-ýêñïåðèìåíòàëüíîãî àíàëèçà âëèÿíèÿ òåìïåðàòóðû íà ìåõàíè÷åñêèå ñâîéñòâà âûñîêîïðî÷íîé êîíñòðóêöèîííîé ñòàëè S690QL. Îïðåäåëåíà ìàêñèìàëüíàÿ òåìïåðàòóðà ïðè ñòàòè÷åñêèõ èñïûòàíèÿõ íà ðàñòÿaeåíèå, ïðè êîòîðîé äàííàÿ ñòàëü ñîõðàíÿåò âûñîêèå ìåõàíè÷åñêèå õàðàêòåðèñòèêè. Ñòàòè÷åñêèå èñïûòàíèÿ íà ðàñòÿaeåíèå ïðîâîäèëèñü ïðè ïÿòè ðàçëè÷íûõ òåìïåðàòóðàõ â äèàïàçîíå 20…550°Ñ. Ïîëó÷åííûå ýêñïåðèìåíòàëüíûå äàííûå ñðàâíèâàëèñü ñ ðåçóëüòàòàìè êîíå÷íîýëåìåíòíûõ ðàñ÷åòîâ ïóòåì ïîñòðîåíèÿ ñîîòâåòñòâóþùèõ êðèâûõ óïðî÷íåíèÿ ñòàëè.Êëþ÷åâûå ñëîâà: ñòàëü S690QL, òåìïåðàòóðà, ìåõàíè÷åñêèå ñâîéñòâà, êîíå÷íîýëåìåíòíûé ÷èñëåííûé àíàëèç, ýêâèâàëåíòíîå íàïðÿaeåíèå, ýôôåêòèâíàÿ äåôîðìàöèÿ.Introduction. With constant advancements in the field of construction engineering, there is a growing need for high strength construction steels such as the steel grade S690QL, which is analyzed in this paper. These steels should have good mechanical properties which would make the construction reliable and light. The steel grade S690QL is used for producing high responsible constructions such as cranes, dynamic loaded parts for millitary vehicles and battle assemblies, etc [1]. When complex constructions are made, especially the ones made of steels of wide cross sections, the steel is often heated (preheated, additionally heated and tempered), and the process engineers and designers often find themselves in a dilemma concerning the maximum temperatures allowed for this process. In the literature, wide ranges of these temperatures can be found, depending on the thickness. The aim of this paper is to determine experimentaly and numericaly the maximum working temperatures at which S690QL steel keep thier high strength values.In order to determine dependance of mechanical properties of the S690QL steel on the temperature, numerous investigations has been carried out [2][3][4][5][6][7]. Most of the investigations dealt with properties of base metal S690QL, but some papers show results of investigation of welded joints made of mentioned steel [2]. The aim of investigations was to determine

Effect of Elevated Temperatures on Mechanical Properties of Ultra High Strength Hot Work Tool Steel H11

“…In fact, the results show a quick reduction in the ultimate tensile strength as soon as 600 °C is exceeded, but the full collapse occurs at 650 °C and above. A similar tendency was discovered in the previous study on the influence of high temperatures on tensile strength of the structural steel S690QL [23], where it was concluded that a decrease in tensile properties occurs at 450 °C. The tensile strength decrease with a temperature increase is expected due to recrystallization and softening.…”

“…The stress integration algorithm for large strain deformations in the isotropic plasticity based on the multiplicative decomposition of the deformation gradient using the logarithmic strains is given in details in [23]. Due to the low plasticity and ultra-high strength of the tested steel it can be concluded that the visible necking is missing up to the temperatures of 650 ºC.…”

Analysis of Selected Properties of Welded Joints of the HSLA Steels

“…The cooling time in that temperature range can be calculated according to different expressions, as well as determined experimentally. Knowing that cooling time and relevant material properties, enables prediction of characteristics of the welded joint and the heat affected zone [23][24][25].…”

Analysis of Influence of the Welding Procedure on Impact Toughness of Welded Joints of the High-Strength Low-Alloyed Steels

“…The cooling time, in that temperature range, can be calculated according to different expressions, as well as determined experimentally. Knowing that cooling time and relevant material properties enables prediction of characteristics of the welded joint and the heat affected zone [22][23][24].…”