We　study　the　structure,　crystallization,　and　performances　of　the　sealing　glasses　with　the　composition　(mol.%)　of　12Al(2)O(3)center　dot　8B(2)O(3)center　dot　40SiO(2)center　dot　40RO　(R　=　Mg,　Ca,　Sr)　for　solid　oxide　fuel　cells　(SOFCs)　before　and　after　isothermal　treatment　at　700　degrees　C,　which　is　within　the　operation　temperature　range　(600-800　degrees　C)　of　SOFCs.　The　crystallization　behavior　has　been　investigated　by　differential　scanning　calorimetry　and　X-ray　diffraction　under　both　dynamic　and　isothermal　conditions.　The　structural　evolution　is　probed　using　the　Raman　and　nuclear　magnetic　resonance　spectroscopies.　The　performances　of　the　sealing　glasses　are　characterized　in　terms　of　the　coefficient　of　thermal　expansion,　the　crystallization-induced　stress　at　glass-steel　interface.　We　find　that　strong　crystallization　occurs　at　the　operation　temperature　(700　degrees　C)　far　below　the　crystallization　onset　temperature　measured　by　DSC.　The　structure　origin　of　this　anomalous　crystallization　is　discussed　in　terms　of　structural　heterogeneity　of　the　three　studied　glasses.　We　determine　the　residual　stress　at　the　interface　between　the　Ca-containing　glass　and　the　steel　after　isothermal　treatment　at　700　degrees　C　for　48　h,　but　this　stress　does　not　lead　to　falling　off　the　glass　layer　from　the　steel.　This　indicates　that　this　glass　is　a　good　candidate　to　be　applied　in　SOFCs.