{"id":2141,"date":"2021-05-07T12:26:20","date_gmt":"2021-05-07T12:26:20","guid":{"rendered":"https:\/\/wldstainless.com\/?p=2141"},"modified":"2021-05-07T12:27:07","modified_gmt":"2021-05-07T12:27:07","slug":"whats-super304h-steel","status":"publish","type":"post","link":"https:\/\/wldstainless.com\/cs\/whats-super304h-steel\/","title":{"rendered":"Co je ocel Super 304H?"},"content":{"rendered":"

S rozvojem ultrakritick\u00fdch jednotek se vysokoteplotn\u00ed pevnost tradi\u010dn\u00edch austenitick\u00fdch nerezov\u00fdch ocel\u00ed typu 18-8 (jako je ocel TP304H) nedok\u00e1zala vyhov\u011bt jejich pot\u0159eb\u00e1m p\u0159i parn\u00edch podm\u00ednk\u00e1ch 600 \u00b0C. Z tohoto d\u016fvodu spole\u010dnost Japan Sumitomo Metal Corporation vyvinula nov\u00e9 materi\u00e1ly pro potrub\u00ed oh\u0159\u00edvac\u00ed plochy kotle jednotky, jako jsou ocel TP347HFG, ocel SUPER304H a ocel HR3C. Ocel Super 304H je nov\u00fdm typem Ocel 18-8<\/a>Pou\u017e\u00edv\u00e1 se zejm\u00e9na p\u0159i v\u00fdrob\u011b p\u0159edeh\u0159\u00edva\u010d\u016f a op\u011btovn\u00fdch oh\u0159\u00edva\u010d\u016f ultrakritick\u00fdch kotl\u016f, jejich\u017e kovov\u00e1 st\u011bna dosahuje teploty nep\u0159esahuj\u00edc\u00ed 700 \u00b0C. V sou\u010dasn\u00e9 dob\u011b tak\u00e9 n\u011bmeck\u00e1 spole\u010dnost Shasqida Mannesmann (d\u0159\u00edve DMV Company) vyr\u00e1b\u00ed podobn\u00e9 ocelov\u00e9 trubice se stupn\u011bm tvrdosti DMV 304HCU.<\/p>\n

Ocel Super304H je ocel se sn\u00ed\u017een\u00fdm obsahem Mn, Si, Cr a Ni na z\u00e1klad\u011b oceli TP304H, p\u0159i\u010dem\u017e p\u0159id\u00e1n\u00edm 2,5% ~ 3,5% Cu a 0,30% ~ 0,60% Nb a 0,05 %~ 0,12% N doch\u00e1z\u00ed k v\u00fdrob\u011b difuzn\u00ed precipitativn\u00ed f\u00e1ze a bohat\u00e9 na m\u011b\u010f f\u00e1zov\u00e9 zpevn\u011bn\u00ed v provozu, doch\u00e1z\u00ed k zes\u00edlen\u00ed v\u00e1pn\u00edkovit\u00fdch zpev\u0148uj\u00edc\u00edch f\u00e1z\u00ed v provozu, a to pomoc\u00ed NbC(N), NbCrN a M23C6, co\u017e v\u00fdrazn\u011b zvy\u0161uje p\u0159\u00edpustn\u00e9 nap\u011bt\u00ed p\u0159i provozn\u00ed teplot\u011b a p\u0159\u00edpustn\u00e9 nap\u011bt\u00ed p\u0159i teplot\u011b 600 ~ 650 \u00b0C je o 30% vy\u0161\u0161\u00ed ne\u017e u oceli TP347H. Obojnost p\u00e1ry p\u0159i oxida\u010dn\u00edm procesu je u tohoto materi\u00e1lu srovnateln\u00e1 s materi\u00e1lem TP347HFG a v\u00fdrazn\u011b lep\u0161\u00ed ne\u017e u materi\u00e1lu TP321H. Je uvedena v ASME Code Case 2328-1, standardu ASTM A-213 a m\u00e1 \u010d\u00edslo S30432.<\/p>\n

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Chemi\u010dka kompozice materi\u00e1lu Super 304H<\/strong><\/p>\n\n\n\n\n
C<\/td>\nSi<\/td>\nMn<\/td>\nP<\/td>\nS<\/td>\nCr<\/td>\nNi<\/td>\nN<\/td>\nAl<\/td>\nB<\/td>\nNb<\/td>\nCu<\/td>\nV<\/td>\nMo<\/td>\n<\/tr>\n
0.08<\/td>\n0.21<\/td>\n0.79<\/td>\n0.03<\/td>\n0.001<\/td>\n18.42<\/td>\n8.66<\/td>\n0.11<\/td>\n0.007<\/td>\n0.004<\/td>\n0.5<\/td>\n2.77<\/td>\n0.04<\/td>\n0.35<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n

Mechanick\u00e9 vlastnosti materi\u00e1lu Super 304H<\/strong><\/p>\n\n\n\n\n
S\u00edla v tahu, MPa<\/td>\nUz\u00e1v\u011brnost, Mpa<\/td>\nProdlou\u017een\u00ed, %<\/td>\n<\/tr>\n
360\/350<\/td>\n640\/645<\/td>\n58\/60<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n

Vzhledem k vysok\u00fdm parametr\u016fm p\u00e1ry v ultra-superkritick\u00fdch jednotk\u00e1ch se st\u00e1v\u00e1 odolnost oceli pou\u017e\u00edvan\u00e9 v tlakov\u00fdch za\u0159\u00edzen\u00edch s vysokou teplotou v\u016f\u010di oxidaci velmi d\u016fle\u017eitou. Obecn\u011b plat\u00ed, \u017ee vnit\u0159n\u00ed st\u011bna ocelov\u00e9 trubky typu super 304H je p\u0159edpra\u0161ov\u00e1na, aby se zlep\u0161ila odolnost proti oxidaci p\u00e1rou. Na vnit\u0159n\u00ed stran\u011b ocelov\u00e9 trubky byla vytvo\u0159ena vrstva s tlou\u0161\u0165kou st\u0159elby 30 \u03bcm a jej\u00ed mikrostruktura byla v porovn\u00e1n\u00ed s mikrostrukturou ocelov\u00e9 trubky bez pra\u0161n\u00e9ho le\u0161t\u011bn\u00ed zdokonalena. Po zkou\u0161ce oxidace p\u00e1rou p\u0159i teplot\u011b 650 \u00b0C a dob\u011b trv\u00e1n\u00ed 600 hodin byla tlou\u0161\u0165ka oxidov\u00e9 vrstvy oceli, kter\u00e1 byla o\u0161et\u0159ena pra\u0161n\u00fdm le\u0161t\u011bn\u00edm, men\u0161\u00ed a hust\u0161\u00ed a odolnost oceli proti oxidaci p\u00e1rou byla zv\u00fd\u0161ena. V sou\u010dasn\u00e9 dob\u011b n\u011bkolik p\u0159edn\u00edch ocel\u00e1ren v \u010c\u00edn\u011b vyrobilo podobnou t\u0159\u00eddu 10CrL8Ni9NbCu3Bn specifikovanou v GB 5310-2008, kter\u00e1 je v sou\u010dasn\u00e9 dob\u011b pou\u017e\u00edv\u00e1na v n\u011bkolika projektech ultra-superkritick\u00fdch jednotek v \u010c\u00edn\u011b.<\/p>","protected":false},"excerpt":{"rendered":"

With the development of ultra-supercritical units, the high-temperature strength of traditional 18-8 Austenitic stainless steels (such as TP304H steel) has been unable to meet their needs with steam parameters of 600\u2103. For this reason, Japan Sumitomo Metal Corporation has developed new materials for the boiler heating surface pipeline of the unit, like TP347HFG steel, SUPER304H […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[],"class_list":["post-2141","post","type-post","status-publish","format-standard","hentry","category-news"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t