{"id":2117,"date":"2021-03-19T08:51:44","date_gmt":"2021-03-19T08:51:44","guid":{"rendered":"https:\/\/wldstainless.com\/?p=2117"},"modified":"2021-03-19T08:51:44","modified_gmt":"2021-03-19T08:51:44","slug":"stainless-steel-321-vs-347","status":"publish","type":"post","link":"https:\/\/wldstainless.com\/cs\/stainless-steel-321-vs-347\/","title":{"rendered":"Nerezov\u00e1 ocel 321 VS 347"},"content":{"rendered":"

Vlastnost nerezov\u00e9 oceli 321 a nerezov\u00e9 oceli 347 je ve v\u011bt\u0161in\u011b p\u0159\u00edpad\u016f podobn\u00e1, nerezov\u00e1 ocel 321 je druh titanu \u2013 stabilizace austenitick\u00e9 nerezov\u00e9 oceli 18\/8 (304), mal\u00e9 mno\u017estv\u00ed titanu ji \u010din\u00ed v rozsahu teplot precipitace karbid\u016f , to je 425-850 \u2103, po zah\u0159\u00e1t\u00ed se neobjevuje mezikrystalov\u00e1 koroze, s dobrou pevnost\u00ed, odolnost\u00ed proti oxida\u010dn\u00edmu odlupov\u00e1n\u00ed a odolnost\u00ed proti korozi ve vod\u011b.<\/p>\n

321H je vysoce uhl\u00edkov\u00e1 verze 321 s vy\u0161\u0161\u00ed pevnost\u00ed p\u0159i vysok\u00fdch teplot\u00e1ch a prim\u00e1rn\u011b se pou\u017e\u00edv\u00e1 pro vysokoteplotn\u00ed aplikace kolem 900 \u00b0C. Nev\u00fdhodou 321 je, \u017ee titan m\u00e1 \u0161patn\u00fd p\u0159echod sva\u0159ovac\u00edho oblouku, tak\u017ee jej nelze pou\u017e\u00edt jako sva\u0159ovac\u00ed materi\u00e1l, zat\u00edmco 347 obsahuj\u00edc\u00ed niob hraje tak\u00e9 roli stabilizace karbidu a lze jej tak\u00e9 p\u0159en\u00e1\u0161et sva\u0159ovac\u00edm obloukem. 347 je standardn\u00ed sva\u0159ovac\u00ed materi\u00e1l pro sva\u0159ov\u00e1n\u00ed nerezov\u00e9 oceli 321 a p\u0159\u00edle\u017eitostn\u011b se pou\u017e\u00edv\u00e1 jako z\u00e1kladn\u00ed kov. Pod\u00edvejme se n\u00ed\u017ee na jejich chemick\u00e9 a mechanick\u00e9 srovn\u00e1n\u00ed:<\/p>\n

 <\/p>\n

Srovn\u00e1n\u00ed chemick\u00e9ho slo\u017een\u00ed<\/strong><\/p>\n\n\n\n\n\n
Zn\u00e1mky<\/td>\nC<\/td>\nMn<\/td>\nSi<\/td>\nP<\/td>\nS<\/td>\nCr<\/td>\nNi<\/td>\nMo<\/td>\nN<\/td>\njin\u00fd<\/td>\n<\/tr>\n
321<\/td>\n0.08<\/td>\n2.00<\/td>\n0.75<\/td>\n0.045<\/td>\n0.03<\/td>\n17.0-19.0<\/td>\n9.0-12.0<\/td>\n\/<\/td>\n0.1<\/td>\nTi=5(C+N)0,7<\/td>\n<\/tr>\n
347<\/td>\n0.08<\/td>\n2.00<\/td>\n0.75<\/td>\n0.045<\/td>\n0.03<\/td>\n17.0-19.0<\/td>\n9.0-13.0<\/td>\n\/<\/td>\n\/<\/td>\nNb = 10 (C+N) 1,0<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Vid\u00edme, \u017ee rozd\u00edl mezi nimi je p\u0159\u00eddavek Ti a Nb. D\u00edky p\u0159id\u00e1n\u00ed stabilizovan\u00e9ho prvku titanu m\u016f\u017ee 321 odolat tvorb\u011b karbidu chr\u00f3mu p\u0159i 426\u2103~815\u2103, tak\u017ee m\u00e1 vynikaj\u00edc\u00ed odolnost proti mezikrystalov\u00e9 korozi a vysokoteplotn\u00ed v\u00fdkon a m\u00e1 vy\u0161\u0161\u00ed te\u010den\u00ed a lomov\u00e9 vlastnosti ne\u017e 304 a 304L. Krom\u011b toho m\u00e1 321 tak\u00e9 dobrou hou\u017eevnatost p\u0159i n\u00edzk\u00fdch teplot\u00e1ch a vynikaj\u00edc\u00ed tvarovatelnost a sva\u0159ovac\u00ed vlastnosti, bez \u017e\u00edh\u00e1n\u00ed po sva\u0159ov\u00e1n\u00ed.<\/p>\n

Nerezov\u00e1 ocel 347 je austenitick\u00e1 nerezov\u00e1 ocel obsahuj\u00edc\u00ed niob a 347H je jej\u00ed verze s vysok\u00fdm obsahem uhl\u00edku. 347 lze pova\u017eovat za verzi s p\u0159\u00eddavkem niobu na b\u00e1zi 304. Nb, prvek vz\u00e1cn\u00fdch zemin, m\u00e1 podobn\u00fd \u00fa\u010dinek jako titan p\u0159i rafinaci zrn, m\u016f\u017ee odol\u00e1vat mezikrystalov\u00e9 korozi a podporovat vytvrzov\u00e1n\u00ed st\u00e1rnut\u00edm.<\/p>\n

 <\/p>\n

Porovn\u00e1n\u00ed fyzik\u00e1ln\u00edch vlastnost\u00ed<\/strong><\/p>\n\n\n\n\n\n
Zn\u00e1mky<\/td>\nPevnost v tahu, Mpa<\/td>\nMez kluzu, Mpa<\/td>\nProdlou\u017een\u00ed (50 mm)<\/td>\nTvrdost, HB<\/td>\n<\/tr>\n
321<\/td>\n515<\/td>\n205<\/td>\n40<\/td>\n217<\/td>\n<\/tr>\n
347<\/td>\n515<\/td>\n205<\/td>\n40<\/td>\n201<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n

Typick\u00e9 aplikace<\/strong><\/p>\n

Nerezov\u00e1 ocel 347&347H m\u00e1 lep\u0161\u00ed vysokoteplotn\u00ed v\u00fdkon ne\u017e 304 a 321. Je \u0161iroce pou\u017e\u00edv\u00e1na v letectv\u00ed, petrochemii, potravin\u00e1\u0159stv\u00ed, pap\u00edrenstv\u00ed a dal\u0161\u00edch pr\u016fmyslov\u00fdch odv\u011btv\u00edch, jako je v\u00fdfukov\u00e9 potrub\u00ed a odbo\u010dka leteck\u00e9ho motoru, potrub\u00ed hork\u00e9ho plynu turb\u00ednov\u00e9ho kompresoru a pr\u00e1ce s d\u00edly p\u0159i n\u00edzk\u00e9 z\u00e1t\u011b\u017ei a teplot\u011b nep\u0159esahuj\u00edc\u00ed 850 \u2103.<\/p>\n

D\u00edky p\u0159id\u00e1n\u00ed titanu do 321 je vhodn\u011bj\u0161\u00ed pro aplikace, kde je pot\u0159eba vysok\u00e1 teplota a dobr\u00e1 odolnost proti korozi. Je vhodn\u00fd pro 304 senzibilizovan\u00e9 a 304L aplikace s nedostate\u010dnou pevnost\u00ed p\u0159i vysok\u00fdch teplot\u00e1ch. Typick\u00e9 aplikace zahrnuj\u00ed tepeln\u00e9 dilata\u010dn\u00ed spoje, vlnovce, sou\u010d\u00e1sti v\u00fdfukov\u00e9ho syst\u00e9mu letadel, pouzdra topn\u00fdch t\u011bles, sou\u010d\u00e1sti pec\u00ed a v\u00fdm\u011bn\u00edky tepla.<\/p>","protected":false},"excerpt":{"rendered":"

Vlastnost nerezov\u00e9 oceli 321 a nerezov\u00e9 oceli 347 je ve v\u011bt\u0161in\u011b p\u0159\u00edpad\u016f podobn\u00e1, nerezov\u00e1 ocel 321 je druh titanu \u2013 stabilizace austenitick\u00e9 nerezov\u00e9 oceli 18\/8 (304), mal\u00e9 mno\u017estv\u00ed titanu ji \u010din\u00ed v rozsahu teplot precipitace karbid\u016f , to je 425-850\u2103, po zah\u0159\u00e1t\u00ed se neobjevuje mezikrystalov\u00e1 koroze, s dobrou pevnost\u00ed, [\u2026]<\/p>","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-2117","post","type-post","status-publish","format-standard","hentry","category-news"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/wldstainless.com\/cs\/wp-json\/wp\/v2\/posts\/2117","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wldstainless.com\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wldstainless.com\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wldstainless.com\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wldstainless.com\/cs\/wp-json\/wp\/v2\/comments?post=2117"}],"version-history":[{"count":2,"href":"https:\/\/wldstainless.com\/cs\/wp-json\/wp\/v2\/posts\/2117\/revisions"}],"predecessor-version":[{"id":2119,"href":"https:\/\/wldstainless.com\/cs\/wp-json\/wp\/v2\/posts\/2117\/revisions\/2119"}],"wp:attachment":[{"href":"https:\/\/wldstainless.com\/cs\/wp-json\/wp\/v2\/media?parent=2117"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wldstainless.com\/cs\/wp-json\/wp\/v2\/categories?post=2117"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wldstainless.com\/cs\/wp-json\/wp\/v2\/tags?post=2117"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}