Heat resistant steel refers to steel with thermal stability and thermal strength under high temperature conditions. Thermal stability refers to the chemical stability (corrosion resistance, non-oxidation) of steel under high temperature conditions. Thermal strength refers to sufficient strength of steel under high temperature conditions. The heat resistance is mainly guaranteed by alloying elements such as chromium, molybdenum, vanadium, titanium na niobium, olsem na ol i mas makim ol samting bilong weldim bihainim ol samting i stap insait long as bilong as metal. Ol i save yusim stiel i no inap hat long instolesen konstraksen bilong petrolium na petrokemikel indastri{{5} yumi save kam long kontek wantaim stiel bilong hat resisten stiel i gat liklik aloi i stap insait, olsem 15CrMo na ol narapela aloi i stap insait, olsem 15CrMo na ol narapela aloi i stap insait, olsem 15CrMo na ol narapela aloi i stap insait, olsem 15CrMo na ol narapela samting olsem 15CrMo na ol narapela samting.
Jenerali, aloi elemen konten we i no kasem 50% oli singaotem hat resistent steel. Japanesem hat resisten steel standet JIS G4311, G4312, antap long sam SUH series standet{{4} Folem difren maekrostrakja blong papa mo mama fasen, austenitis steel i save stap long stiel we i no save kasem hat, i save mekem se hem i no save stanap strong long stiel we i save stanap strong long hat blong hem. stiel i no inap long hat i no inap long kisim SUH seris seris hat resisten kast stiel, tasol i no klasim mak bilong ain bihainim papamama fez straksa, na miksim feritik hat resisten stiel, martensitik hat resisten stiel na austenitik hat resisten stiel wantaim.
Stil we i no inap hat tumas.
Representativ feritik hat resisten stiel ol i save yusim em SUS430 wantaim liklik C-17Kr. Cr em i element we inap long kamapim gutpela hai tempereja korosen resistens bilong stiel na em i wanpela indipesen element long hat resistant stiel. SUS430 i no gat gutpela oksidesen resistens{5} SUS430 em i no gat bikpela pe long stiel i no gat strong long stiel i no gat strong long stiel i no gat strong long en. i hat bihain long taim bilong en i go daun tru, na strong bilong en i no hat tumas, olsem na ol i ken yusim tasol long ol hap we i no nidim planti strong. Long narapela sait, long wanem, thermal ekspansen koefisen bilong SUS430 i liklik, na wok bilong skruim hat bilong hat i go insait better. In addition, when SUS430 is used for a long time at about 500℃, embrittlement will occur due to the precipitation of brittle phase, which should be paid attention to. In addition, Al is also an element that enhances antioxidant capacity. At high temperature, Al forms Al2O3 on the surface of the oxide sheet, which becomes a strong protective film and plays a role in improving the oksidesen resistens. stiel i no inap hat long yusim dispela wok bilong Al em FCH1. FCH1 em i wanpela stiel i resis long hat wantaim 5%A ol i putim insait long 25%Cr steel. Em i gat gutpela oksidesen resistens aninit long 1200 digri .
Stil we i no inap long hat.
Ol stiel bilong martensit i save daunim hat bilong hat em 12%Kr stiel SUS403 na SUS410J1 wantaim samting olsem 0{{5}1% kabon konten. Ol dispela stiel i no inap long hat i pas strong long bikpela mak bilong hat bilong papamama, na bihain ol i no inap long mekim wok bilong lukautim M23C6 i go antap long taim bilong mekim M23C6 i kamap strong long M23C6. . Sapos ol i putim Mo long mekim gutpela moa long daunim strong bilong daunim belhat, bikpela strong i ken stap moa (13}} Martensitic hat resisten stiel bai mekim isi long bikpela tempereja antap long 500-600 digri , na dispela i kamapim bikpela daunbilo long strong bilong. Long taim bilong en, em i gutpela long mekim wok bilong en i go daunbilo long500-600 digri long taim bilong bikpela tempereja bilong en. bikos kromium konten bilong martensitic hat resistant stiel i liklik (12%), na hap bilong kromium i stap yet long karbaid, i no inap long garantiim kromium konten insait long papamama fez, olsem na oksidesen resistens bilong martensitik hat resisten stiel i save liklik moa long stiel bilong ferritik hat long martensit stiel na austenik hit resisten stiel i {18} Si na austenik hat resisten stiel i {18} Si na austenik hat resisten stiel long afetten stiel{18} Si na austenik hat resisten stiel long afetten stiel{18} Si na austenik hat resisten stiel long afetten stiel i {18} Si na austenititik hat resisten stiel i save holim stiel bilong martensiti. stiel i no inap long mekim ol steel i no inap bagarap, em SUH3 na SUH11 martensitic hat resisten stiel wantaim Si i skruim long kamapim gut oksidesen resistens bilong ol. Ol dispela stiel i no inap long kisim hat ol i yusim long ol enjin intake valv na ol bolt i no inap hat.
Stil we i no inap hat long hat
Ol i putim Cr long stiel i go wantaim long taim ol i putim ol samting bilong helpim ol manmeri bilong Austenite i stap gut Ni, na dispela i mekim na stebol stebol austenit straksa long olgeta tempereja. Ol stein bilong austenitik straksa i stap long SUS304 na SUS{2} olsem yumi olgeta i save, SUS304 em i no inap long yusim ol steinles stiel bilong hatim het. 600 digri , strong bilong strongpela ain i no inap hat long hat na i no inap long kisim hat, em i stap namel long ain bilong daunim hat bilong martensit, na antap long 600 digri , strong i bikpela moa long stiel i no inap kisim hat bilong martensit. taim ol i yusim longpela taim long 700-900 digri , bai i gat liklik hap bilong pes i go daun, bai ol samting i kamap britel. Antap long dispela, long wanem, thermal ekspansen koefisen bilong SUS304 na SUS310 i bikpela moa long ol stiel bilong martensitic na feritik hat i mas kisim pe bilong tupela poin, em i kisim bagarap long tupela poin bilong tupela poin, em i kisim bagarap long dispela tupela hap bilong tupela poin, em i kisim bagarap long dispela tupela hap bilong tupela poin, em i kisim bagarap long dispela tupela hap bilong tupela poin, em i mas kisim bagarap long tupela poin bilong tupela poin, em i kisim bagarap long tupela poin bilong tupela poin, em i kisim bagarap long tupela poin bilong tupela poin, em i kisim bagarap long tupela poin, em i kisim bagarap long tupela poin, em i kisim bagarap long tupela poin, em i kisim bagarap long tupela poin, em i kisim bagarap long tupela poin, em i kisim bagarap long tupela poin, em i kisim bagarap long tupela poin.
Taim ol i nidim bikpela tempereja strong, strong bilong austenitik hat resisten stiel i ken kamap strong moa long rot bilong strongim presipitesen na strongim rot bilong strongim bel{{0} Austenitik hat resisten stiel ol i yusim long enjin eksos valv em SUH{{1} Bikpela hat tempereja strong bilong SUH35 i bin kamap gutpela moa long rot bilong strongim C long stiel i strongim na strongim rot bilong stretim hevi long rot bilong putim C long stiel i stap strong na strongpela rot bilong stretim hevi long rot bilong putim C long stiel i stap strong na strongpela rot bilong stretim hevi long rot bilong putim C long stiel i stiel i strongim na strongpela rot bilong stretim hevi bilong en. i 4% long rot bilong skruim ol samting i stap insait long Mn. SUH660 ol i yusim long ol bolt na spring bilong hat i no inap hat moa, i kamap strong moa long rot bilong ren bilong 'feis (Ni3 (Al, Ti)) bikos ol i putim Al na T.
Precipitate strong stiel we i no inap long hat.
The representative brand of martensitic heat resistant steel is SUS630. After aging at 500℃, ε phase (Cu phase) precipitate in low C martensite parent phase of SUS630 to improve the strength of steel. However, when the temperature exceeds 500℃, the ε phase becomes coarser and the martensite structure changes, which results in the decrease of steel strength. Olsem na, ol i save yusim SUS630 moa yet long ol hap bilong tabin aninit long 500 digri . Bikpela hap bilong SUS630 stiel em 17Cr-4Ni{12}}Cu, ol Ni konten i no antap tumas, na tingim strong bilong austenite, olsem na em i no wanpela risos-sevim divelopmen steel{14}} .
