{"id":2121,"date":"2021-03-31T08:52:53","date_gmt":"2021-03-31T08:52:53","guid":{"rendered":"https:\/\/wldstainless.com\/?p=2121"},"modified":"2021-03-31T09:06:23","modified_gmt":"2021-03-31T09:06:23","slug":"302hq-vs-304-stainless-steel","status":"publish","type":"post","link":"https:\/\/wldstainless.com\/cs\/302hq-vs-304-stainless-steel\/","title":{"rendered":"302HQ vs. 304 nerezov\u00e1 ocel"},"content":{"rendered":"

Nerezov\u00e1 ocel 302HQ je standardn\u00ed materi\u00e1l pou\u017e\u00edvan\u00fd zejm\u00e9na p\u0159i v\u00fdrob\u011b samorezn\u00fdch \u0161roub\u016f a lehk\u00fdch mechanick\u00fdch \u0161roub\u016f. Pou\u017e\u00edv\u00e1 se tak\u00e9 v \u0161roubech, z\u00e1v\u011bsn\u00fdch \u0161roubech, nit\u00edch a speci\u00e1ln\u00edch spojovac\u00edch prvc\u00edch. N\u00e1zev 302HQ nen\u00ed standardizovan\u00fd. ASTM jej uv\u00e1d\u00ed jako UNS S30430, p\u0159i\u010dem\u017e zahrnuje tak\u00e9 \u201eXM-7\u201c, \u201e304CU\u201c a \u201e304HQ\u201c. Nyn\u00ed zcela nahradil ocel 384 a 305 pro \u00fa\u010dely studen\u00e9ho oh\u00fdb\u00e1n\u00ed. Norma ISO 3506, Standardn\u00ed specifikace pro spojovac\u00ed prvky z nerezov\u00e9 oceli, 302HQ jako vhodn\u00e1 sou\u010d\u00e1st pro spojovac\u00ed prvky t\u0159\u00eddy \u201eA2\u201c; b\u011b\u017en\u011b se pou\u017e\u00edv\u00e1 k v\u00fdrob\u011b spojovac\u00edch prvk\u016f v pevnosti A2-70 a A2-80. Stabiln\u00ed austenitick\u00e1 struktura umo\u017e\u0148uje pou\u017e\u00edt 302HQ i po rozs\u00e1hl\u00e9m tepeln\u00e9m zpracov\u00e1n\u00ed bez magnetismu a z\u00e1rove\u0148 udr\u017eovat vynikaj\u00edc\u00ed hou\u017eevnatost p\u0159i teplot\u00e1ch a\u017e do bodu mrazu. Ve srovn\u00e1n\u00ed s nerezovou ocel\u00ed 304 m\u016f\u017ee p\u0159id\u00e1n\u00ed 3 procent m\u011bdi v 302HQ v\u00fdrazn\u011b sn\u00ed\u017eit rychlost ztvrdnut\u00ed p\u0159i tepeln\u00e9m zpracov\u00e1n\u00ed. Chemick\u00e9 slo\u017een\u00ed a fyzik\u00e1ln\u00ed vlastnosti jsou uvedeny n\u00ed\u017ee:<\/p>\n

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Ekvivalentn\u00ed materi\u00e1l<\/strong><\/p>\n\n\n\n\n
Zp\u011btn\u00e9 hodnocen\u00ed<\/td>\nUNS No<\/td>\nDIN<\/td>\nEN<\/td>\nJIS<\/td>\n<\/tr>\n
302HQ<\/td>\nS30430<\/td>\n1.4567<\/td>\nX3CrNiCu18-9-4<\/td>\nSUSXM7<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

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Chemick\u00e1 kompozice (ASTM A493 S30430)<\/strong><\/p>\n\n\n\n\n
Zp\u011btn\u00e9 hodnocen\u00ed<\/td>\nC<\/td>\nMn<\/td>\nSi<\/td>\nP<\/td>\nS<\/td>\nCr<\/td>\nMo<\/td>\nNi<\/td>\nCu<\/td>\n<\/tr>\n
302HQ<\/td>\n0.03<\/td>\n2.00<\/td>\n1.00<\/td>\n0.045<\/td>\n0.03<\/td>\n17.0-19.0<\/td>\n\/<\/td>\n8.0-10.0<\/td>\n3.0-4.0<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

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Mechanick\u00e9 vlastnosti<\/strong><\/p>\n

S\u00edla v tahu 302HQ: Zk\u00e1pnut\u00ed: 605, M\u00edrn\u00e9 tv\u00e1\u0159en\u00ed: 660<\/p>\n

Hustota: 7900 kg\/m\u00b2<\/p>\n

Modul pru\u017enosti: 193 GPa<\/p>\n

Pr\u016fm\u011brn\u00fd koeficient tepeln\u00e9ho rozp\u00edn\u00e1n\u00ed: 0\u2013100 \u00b0C (um\/m\/\u00b0C) 17,2; 0\u2013315 \u00b0C (um\/m\/\u00b0C); 0\u2013538 \u00b0C (18,8)<\/p>\n

Teplotn\u00ed vodivost: 100 \u00b0C (W\/M.K) 16,3; 500 \u00b0C (W\/M.K) 21,5<\/p>\n

Specifick\u00e1 teplota: 0\u2013100 \u00b0C (J\/kg.K) 500;<\/p>\n

Odolnost: 720<\/p>\n

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Odolnost proti korozi<\/strong><\/p>\n

Jeho odolnost proti korozi je ekvivalentn\u00ed nebo lep\u0161\u00ed ne\u017e u nerezov\u00e9 oceli 304. V tepl\u00e9m chlorn\u00e9m prost\u0159ed\u00ed se snadno vyskytuje vrz\u00e1n\u00ed a koroze v d\u00edr\u00e1ch, zat\u00edmco v\u0159eten\u00ed v nap\u011bt\u00ed je citliv\u00e9 p\u0159i teplot\u00e1ch vy\u0161\u0161\u00edch ne\u017e asi 50 \u00b0C. 302HQ dok\u00e1\u017ee odol\u00e1vat chloridu ve vod\u011b pitn\u00e9 v mno\u017estv\u00ed p\u0159ibli\u017en\u011b 200 mg\/l p\u0159i pokojov\u00e9 teplot\u011b a 150 mg\/l p\u0159i teplot\u011b 60 \u00b0C.<\/p>\n

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Vysok\u00e1 odolnost v\u016f\u010di teplot\u00e1m<\/strong><\/p>\n

Dobr\u00e1 oxida\u010dn\u00ed odolnost, intermitentn\u00ed provoz p\u0159i teplot\u011b a\u017e 870 \u00b0C, nep\u0159etr\u017eit\u00fd provoz p\u0159i teplot\u011b a\u017e 925 \u00b0C. Vzhledem k n\u00edzk\u00e9mu obsahu uhl\u00edku v materi\u00e1lu 302HQ je vhodn\u00fd pro nep\u0159etr\u017eit\u00fd provoz (bez precipitace karbid\u016f) v rozmez\u00ed teplot od 425 do 860 \u00b0C.<\/p>\n

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O\u0161et\u0159en\u00ed hork\u00fdm vzduchem<\/strong><\/p>\n

L\u00e9kov\u00e1 \u00faprava (zafouknut\u00ed) se zah\u0159\u00edv\u00e1 na teplotu 1010\u20131120 \u00b0C a rychle se ochlazuje. L\u00e9k\u00e1rensk\u00e9 \u00fapravy ho nezpevn\u00ed.<\/p>\n

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Sva\u0159itelnost<\/strong><\/p>\n

Vynikaj\u00edc\u00ed sva\u0159itelnost. K sva\u0159ov\u00e1n\u00ed lze pou\u017e\u00edt v\u0161echny standardn\u00ed metody f\u00faze (a\u0165 u\u017e s plniv\u00fdm kovem nebo bez n\u011bj). Pou\u017eijte elektrodu 308L. Sva\u0159ov\u00e1n\u00ed obvykle nen\u00ed nutn\u00e9, s v\u00fdjimkou v\u00fdroby \u0161roubov\u00fdch spojovac\u00edch prost\u0159edk\u016f, kde se pro spojen\u00ed dr\u00e1t\u016f pou\u017e\u00edv\u00e1 rezistivn\u00ed spojovac\u00ed proces butt welding.<\/p>\n

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Zpracov\u00e1n\u00ed\u00a0<\/strong><\/p>\n

Modul 302HQ se jen z\u0159\u00eddka obr\u00e1b\u00ed. Tento typ materi\u00e1lu m\u00e1 velmi n\u00edzk\u00fd obsah s\u00edry, co\u017e pom\u00e1h\u00e1 zlep\u0161it jeho tvarovatelnost, ale sni\u017euje jeho zpracovatelnost. Vylep\u0161en\u00fd modul 302HQ (UGIMA 4567) m\u00e1 velmi vysokou zpracovatelnost, o n\u011bco vy\u0161\u0161\u00ed obsah s\u00edry a je tak\u00e9 kalcium o\u0161et\u0159en\u00fd pro pou\u017eit\u00ed vy\u017eaduj\u00edc\u00ed rozs\u00e1hl\u00e9 opracov\u00e1n\u00ed za studena a obr\u00e1b\u011bn\u00ed. Ocel 18\/8<\/a>.<\/p>\n

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Studen\u00e1 zpracov\u00e1n\u00ed tvrdnut\u00ed<\/strong><\/p>\n

302HQ je nejni\u017e\u0161\u00ed m\u00edrou tvrzen\u00ed mezi b\u011b\u017en\u00fdmi t\u0159\u00eddami austenitick\u00fdch nerezov\u00fdch ocel\u00ed. Podle \u00fadaj\u016f o tv\u00e1\u0159en\u00ed dr\u00e1tu se pevnost v tahu zv\u00fd\u0161\u00ed o 8 MPa p\u0159i sn\u00ed\u017een\u00ed plochy pro studen\u00e9 zpracov\u00e1n\u00ed o 1%). I po rozs\u00e1hl\u00e9m studen\u00e9m opracov\u00e1n\u00ed z\u016fst\u00e1v\u00e1 zna\u010dka v podstat\u011b odoln\u00e1 v\u016f\u010di magnet\u016fm. N\u011bkter\u00e9 \u0161rouby pro vysokou pevnost s studen\u00fdm oh\u00fdb\u00e1n\u00edm vy\u017eaduj\u00ed ni\u017e\u0161\u00ed m\u00edru tvrzen\u00ed, tak\u017ee 304<\/a> nebo by se m\u00edsto 302HQ m\u011blo pou\u017e\u00edt 304L (nebo speci\u00e1ln\u00ed t\u0159\u00edda 304M); m\u00edra tvrzen\u00ed t\u011bchto t\u0159\u00edd je p\u0159ibli\u017en\u011b 10\u201312,5 MPa.<\/p>\n

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

V\u0161echny aplikace s tvrd\u00fdm h\u0159\u00ed\u017een\u00edm, v\u010detn\u011b samorezn\u00fdch \u0161roub\u016f, st\u0159e\u0161n\u00edch \u0161roub\u016f, mechanick\u00fdch \u0161roub\u016f, \u0161roub\u016f s mont\u00e1\u017en\u00edm krou\u017ekem, blindov\u00fdch nit\u00ed apod.<\/p>","protected":false},"excerpt":{"rendered":"

302HQ stainless steel is a standard material specifically used in the manufacture of self-tapping screws and light mechanical screws. It is also used in bolts, setting screws, rivets, and special fasteners. The name 302HQ is not standardized. The ASTM lists it as UNS S30430, which also includes “XM-7”, “304CU”, and “304HQ”. It has now completely […]<\/p>\n","protected":false},"author":1,"featured_media":2123,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[],"class_list":["post-2121","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t