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Mullite material is a material commonly used in honeycomb regenerator, because in the process of using material under big temperature difference effect, so have a great demand for its thermal shock resistance. The used mullite ceramics were made by the direct solid phase sintering method, and the modulus of elasticity of the mullite ceramics measured by ultrasonic pulse-echo method in a thermal shock and thermal fatigue experiment, respectively. In the air-cooling condition, the study found the mullite ceramic without thermal shock that the longitudinal wave velocity and shear wave velocity respectively 3970(m/s) and 2492(m/s). After 45 times thermal shock of temperature difference of 800°C, longitudinal wave velocity and shear wave velocity decreased to 3910(m/s) and 2457(m/s), and the value of the modulus of elasticity changed 1020MPa. By observing the change of the elastic modulus value rule, can know the elastic deformation of thermal shock on the material performance of thermal shock damage. Moreover, the results can provide the data basis for the calculation of the residual strength and the numerical simulation of thermal stress.

For study the damage characteristic of the mullite heat storage ceramic under thermal shock condition, mechanical properties of mullite have been investigated. Under the different cooling mediums (room temperature water, boiling water, air), single and five cycles thermal shock conditions, The article studied the variation of flexural strength and fracture toughness along with temperature. The result show that with the increase of heat transfer coefficient of cooling medium, the bending strength of ceramic decreased. In the 600°C,the ceramic have a maximum bending strength and a minimum fracture toughness. The fracture toughness of precrack specimen is lower than that of non-precrack specimen on the whole. Both Precrack ceramic and non-precrack ceramic have a maximum fracture toughness at 400°C. The study of this paper provides a theoretical basis for the better predicting fracture damage and service life of heat storage ceramic.

à Ôàêóëüòåò ïðîåêòèðîâàíèÿ äîðîã è òðàíñïîðòíûõ ñðåäñòâ, Øàíüäóíñêèé óíèâåðñèòåò òåõíîëîãèé, Öçûáî, Êèòàé á Ôàêóëüòåò ýëåêòðîìàøèíîñòðîåíèÿ è ýëåêòðîíèêè, Öçûáîñêèé ïðîôåññèîíàëüíûé èíñòèòóò, Öçûáî, Êèòàé Ïðè ðàáîòå ÿäåðíîãî ðåâåðñ-ïîòî÷íîãî ðåàêòîðà êåðàìè÷åñêèå ñîòîâûå ðåãåíåðàòîðû ïîäâåðãàþòñÿ äåéñòâèþ òåðìîóäàðíîé íàãðóçêè. Ñ ïîìîùüþ ïðîãðàììíîãî îáåñïå÷åíèÿ CFX ïðîâåäåíî ÷èñëåííîå ìîäåëèðîâàíèå ýïþð òåìïåðàòóðû è òåìïåðàòóðíîãî íàïðÿaeåíèÿ êåðà-ìè÷åñêèõ ñîòîâûõ ðåãåíåðàòîðîâ. Èññëåäîâàíî èçìåíåíèå òåìïåðàòóð âî âðåìåíè äëÿ êåðà-ìè÷åñêèõ ñîòîâûõ ðåãåíåðàòîðîâ ñ îòâåðñòèÿìè ðàçëè÷íîé ôîðìû. Ïðîàíàëèçèðîâàíû ýïþðû òåìïåðàòóðíîãî íàïðÿaeåíèÿ ðåãåíåðàòîðîâ ñ ðàçíûìè êîíñòðóêöèîííûìè è ýêñïëóàòàöèîííûìè ïàðàìåòðàìè. Óñòàíîâëåíî, ÷òî òåìïåðàòóðíîå íàïðÿaeåíèå êåðàìè÷åñêîãî ñîòîâîãî ðåãåíåðàòîðà çàâèñèò îò ôîðìû îòâåðñòèé, ïîðèñòîñòè è òîëùèíû ñòåíîê. Ðåçóëüòàòû äàííîãî èññëåäîâàíèÿ ñëóaeàò òåîðåòè÷åñêîé áàçîé äëÿ îïòèìèçàöèè êåðàìè-÷åñêèõ ñîòîâûõ ðåãåíåðàòîðîâ.

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