{"id":20412,"date":"2026-05-21T10:00:57","date_gmt":"2026-05-21T02:00:57","guid":{"rendered":"https:\/\/www.worldia-tools.com\/?p=20412"},"modified":"2026-07-13T14:36:32","modified_gmt":"2026-07-13T06:36:32","slug":"how-do-pcbn-turning-inserts-perform-under-high-temperature-conditions-in-hard-turning-processes","status":"publish","type":"post","link":"https:\/\/www.worldia-tools.com\/cs\/how-do-pcbn-turning-inserts-perform-under-high-temperature-conditions-in-hard-turning-processes\/","title":{"rendered":"Jak PCBN soustru\u017en\u00e9 vlo\u017eky prov\u00e1d\u011bj\u00ed p\u0159i vysok\u00fdch teplot\u00e1ch v t\u011b\u017ek\u00fdch soustru\u017en\u00edch procesech?"},"content":{"rendered":"

\"PCBN-vlo\u017eky(2)\"<\/p>\n

Co se stane s PCBN soustru\u017en\u00fdmi vlo\u017ekami b\u011bhem vysokoteplotn\u00edho tvrd\u00e9ho soustru\u017een\u00ed?<\/b><\/strong><\/h2>\n

P\u0159\u00edroda vysokoteplotn\u00edch prost\u0159ed\u00ed p\u0159i tvrd\u00e9m soustru\u017een\u00ed<\/b><\/strong><\/h3>\n

Tvrd\u00e9 soustru\u017een\u00ed je zku\u0161en\u00e1 metoda obr\u00e1b\u011bn\u00ed, kter\u00e1 \u0159eze tvrd\u00e9 materi\u00e1ly rychl\u00fdmi rychlostmi. Tento proces v\u017edy vytv\u00e1\u0159\u00ed intenzivn\u00ed teplo v oblasti \u0159ez\u00e1n\u00ed. T\u0159en\u00ed mezi n\u00e1strojem a obrobkem m\u016f\u017ee zv\u00fd\u0161it teplotu p\u0159es 800 \u00b0C. V\u00fdsledkem je velmi n\u00e1ro\u010dn\u00e9 tepeln\u00e9 nastaven\u00ed. V t\u011bchto situac\u00edch b\u011b\u017en\u00e9 \u0159ezac\u00ed n\u00e1stroje \u010dasto ztr\u00e1cej\u00ed tvrdost nebo za\u017e\u00edvaj\u00ed rychlej\u0161\u00ed opot\u0159eben\u00ed. Ale... PCBN (polykrystalick\u00fd kubick\u00fd nitrid bora) soustru\u017en\u00e9 vlo\u017eky<\/b><\/u><\/strong><\/a>\u00a0Jsou vyrobeny tak, aby zvl\u00e1dly tyto zv\u00fd\u0161en\u00e9 teploty. Udr\u017euj\u00ed si svou s\u00edlu a v\u00fdsledky i p\u0159i siln\u00fdch tepeln\u00fdch tlakech.<\/p>\n

Jak vlastnosti materi\u00e1lu PCBN reaguj\u00ed na zv\u00fd\u0161en\u00e9 teploty<\/b><\/strong><\/h3>\n

Kubick\u00fd nitrid bor (CBN) byl poprv\u00e9 vyroben v roce 1957. Stal se \u010derstv\u00fdm druhem um\u011bl\u00e9ho supertvrd\u00e9ho materi\u00e1lu. Je zn\u00e1m jako druh\u00fd nejtvrd\u0161\u00ed materi\u00e1l po diamantu. Jeho mikrotvrdost spad\u00e1 mezi HV8000-9000 pro jednotliv\u00e9 krystaly. Pro kompozity PCBN je to HV2500-5000. Tato vestav\u011bn\u00e1 tvrdost umo\u017e\u0148uje vlo\u017ek\u00e1m PCBN udr\u017eet svou \u0161pi\u010dku p\u0159i vysok\u00fdch teplot\u00e1ch. Karbidov\u00e9 nebo keramick\u00e9 n\u00e1stroje by tam dali.
\nCBN vykazuje silnou odolnost v\u016f\u010di oxidaci. Neoxiduje se ani p\u0159i 1000 \u00b0C. Tak\u00e9 se vyh\u00fdb\u00e1 chemick\u00fdm reakc\u00edm s \u017eelezn\u00fdmi materi\u00e1ly p\u0159i 1200 ~ 1300 \u00b0 C. Tyto vlastnosti zaji\u0161\u0165uj\u00ed, \u017ee n\u00e1stroje PCBN udr\u017euj\u00ed chemickou stabilitu a bojuj\u00ed proti difuzn\u00edmu opot\u0159eben\u00ed b\u011bhem tvrd\u00fdch soustru\u017en\u00edch prac\u00ed. Krom\u011b toho jejich dobr\u00e1 tepeln\u00e1 vodivost pom\u00e1h\u00e1 p\u0159i dobr\u00e9m \u0161\u00ed\u0159en\u00ed tepla z \u0159ezn\u00e9 z\u00f3ny. To sni\u017euje pravd\u011bpodobnost oh\u00fdb\u00e1n\u00ed n\u00e1stroje nebo tepeln\u00e9ho rozd\u011blen\u00ed.<\/p>\n

\"Pevn\u00e9<\/p>\n

Pro\u010d PCBN Ot\u00e1\u010dec\u00ed vlo\u017eky udr\u017eovat v\u00fdkon, kdy\u017e teplo stoup\u00e1?<\/b><\/strong><\/h2>\n

Mechanismy za tepeln\u00fdm odporem vlo\u017eek PCBN<\/b><\/strong><\/h3>\n

Velk\u00e1 tepeln\u00e1 odolnost vlo\u017eek PCBN poch\u00e1z\u00ed z jejich pevn\u00e9 kovalentn\u00ed vazby v krystalech kubick\u00e9ho nitridu bora. Toto atomov\u00e9 uspo\u0159\u00e1d\u00e1n\u00ed nab\u00edz\u00ed lep\u0161\u00ed ochranu p\u0159ed zm\u011bk\u010den\u00edm pod siln\u00fdm teplem. Nav\u00edc mal\u00e1 chemick\u00e1 vazba mezi CBN a \u017eelezn\u00fdmi materi\u00e1ly sni\u017euje difuzn\u00ed opot\u0159eben\u00ed. Jedn\u00e1 se o b\u011b\u017en\u00fd probl\u00e9m p\u0159i \u0159ez\u00e1n\u00ed tvrzen\u00fdch ocel\u00ed. Stabiln\u00ed mikrostruktura PCBN tak\u00e9 zastavuje oxidaci i po dlouh\u00e9m tepeln\u00e9m kontaktu. Proto zaru\u010duje rovnom\u011brn\u00e9 v\u00fdsledky p\u0159i stabiln\u00edm nebo rozbit\u00e9m tvrd\u00e9m ot\u00e1\u010den\u00ed.<\/p>\n

Jak\u00e9 jsou vzorce opot\u0159eben\u00ed pozorov\u00e1ny p\u0159i vysokoteplotn\u00edm \u0159ez\u00e1n\u00ed?<\/b><\/strong><\/h3>\n

P\u0159i zv\u00fd\u0161en\u00fdch teplot\u00e1ch pat\u0159\u00ed obvykl\u00e9 typy opot\u0159eben\u00ed bo\u010dn\u00ed opot\u0159eben\u00ed, opot\u0159eben\u00ed kr\u00e1teru a mal\u00e9 t\u0159pyten\u00ed hran. Oxida\u010dn\u00ed opot\u0159eben\u00ed m\u016f\u017ee doj\u00edt v t\u011b\u017ek\u00fdch podm\u00ednk\u00e1ch. P\u0159esto postupuje mnohem pomaleji na n\u00e1stroj\u00edch PCBN kv\u016fli jejich z\u00e1kladn\u00ed chemick\u00e9 stabilit\u011b. Pou\u017eit\u00edm spr\u00e1vn\u00fdch metod chlazen\u00ed, jako jsou nastaven\u00ed vzduchov\u00e9ho trysk\u00e1n\u00ed, nebo volbou zp\u016fsob\u016f such\u00e9ho obr\u00e1b\u011bn\u00ed nastaven\u00fdch pro vlo\u017eky PCBN, mohou v\u00fdrobci d\u00e1le prodlou\u017eit \u017eivotnost n\u00e1stroje. Z\u00e1rove\u0148 zachov\u00e1vaj\u00ed p\u0159esnost velikosti.<\/p>\n

Jak \u0159ezn\u00e9 parametry ovliv\u0148uj\u00ed v\u00fdkon vlo\u017eky PCBN?<\/b><\/strong><\/h2>\n

\u00da\u010dinek rychlosti \u0159ez\u00e1n\u00ed a rychlosti pod\u00e1v\u00e1n\u00ed na \u017eivotnost n\u00e1stroje<\/b><\/strong><\/h3>\n

Nastaven\u00ed \u0159ez\u00e1n\u00ed maj\u00ed kl\u00ed\u010dovou roli p\u0159i rozhodov\u00e1n\u00ed o tom, jak p\u016fsob\u00ed soustru\u017en\u00e9 vlo\u017eky PCBN v t\u011b\u017ek\u00fdch teplotn\u00edch podm\u00ednk\u00e1ch. Rychlej\u0161\u00ed rychlosti \u0159ez\u00e1n\u00ed \u010dasto zvy\u0161uj\u00ed teploty. Ale mohou l\u00e9pe povrchov\u00e9 \u00fapravy, pokud jsou dob\u0159e manipulov\u00e1ny. Na druh\u00e9 stran\u011b p\u0159\u00edli\u0161 vysok\u00e9 rychlosti pod\u00e1v\u00e1n\u00ed p\u0159in\u00e1\u0161ej\u00ed mechanick\u00fd tlak, kter\u00fd urychluje opot\u0159eben\u00ed okraj\u016f. Jemn\u00e9 nalazen\u00ed obou nastaven\u00ed umo\u017e\u0148uje dobr\u00fd mix mezi v\u00fdstupem a d\u00e9lkou n\u00e1stroje.
\nNavrhovan\u00e9 podm\u00ednky \u0159ez\u00e1n\u00ed pro Worldia Coated PCBN CNC Inserts nazna\u010duj\u00ed, \u017ee PNH0120 je vhodn\u00fd pro stabiln\u00ed obr\u00e1b\u011bn\u00ed p\u0159i rychlostech od 150 do 250 m\/min. Pou\u017e\u00edv\u00e1 rychlosti pod\u00e1v\u00e1n\u00ed 0,03 do 0,2 mm\/min. Tyto detaily zd\u016fraz\u0148uj\u00ed, jak p\u0159esn\u00e1 volba nastaven\u00ed p\u0159\u00edmo ovliv\u0148uje stabilnost n\u00e1stroje p\u0159i vysokoteplotn\u00edm tvrd\u00e9m soustru\u017een\u00ed.<\/p>\n

\"Pevn\u00e9<\/p>\n

Ovliv\u0148uje tvrdost obrobku tepeln\u00e9 chov\u00e1n\u00ed?<\/b><\/strong><\/h3>\n

T\u011bsnost obrobku v\u00fdrazn\u011b m\u011bn\u00ed tvorbu teploty b\u011bhem obr\u00e1b\u011bn\u00ed. Velmi tvrd\u00e9 materi\u00e1ly, jako je tvrzen\u00e1 ocel, vytv\u00e1\u0159ej\u00ed v\u00edce t\u0159en\u00ed ne\u017e m\u011bkk\u00e9 kovy. P\u0159esto PCBN vlo\u017eky udr\u017eovat p\u0159esnost velikosti navzdory t\u011bmto zm\u011bn\u00e1m. Je to zp\u016fsobeno jejich vysokou \u010dervenou tvrdost\u00ed a pevnou strukturou. V\u00fdb\u011br spr\u00e1vn\u00e9 t\u0159\u00eddy vlo\u017eky \u2013 nap\u0159\u00edklad Worldia PNH2018 nebo PNH3019, vyroben\u00e9 pro r\u016fzn\u00e9 \u00farovn\u011b p\u0159eru\u0161en\u00ed \u2013 je nezbytn\u00fd pro dosa\u017een\u00ed stabiln\u00edch v\u00fdsledk\u016f v r\u016fzn\u00fdch \u00farovn\u00edch hou\u017eevnatosti.<\/p>\n

Jak mohou v\u00fdrobci optimalizovat pou\u017e\u00edv\u00e1n\u00ed vlo\u017eek PCBN v hork\u00fdch podm\u00ednk\u00e1ch?<\/b><\/strong><\/h2>\n

Strategie pro zv\u00fd\u0161en\u00ed \u017eivotnosti n\u00e1stroje v prost\u0159ed\u00ed s vysok\u00fdm teplem<\/b><\/strong><\/h3>\n

Chcete-li z\u00edskat nejlep\u0161\u00ed v\u00fdstup p\u0159i pou\u017eit\u00ed vlo\u017eek PCBN v pou\u017eit\u00ed vy\u017eaduj\u00edc\u00edm teplo, m\u011blo by se prov\u00e9st n\u011bkolik krok\u016f:<\/p>\n