Sintering shine bugun zuciya na ƙarfe na foda-inda sako-sako da foda na ƙarfe ya zama mai yawa, kayan aikin aiki. A wurin aikinmu na Qingdao, mun ƙaddamar da batches sama da 12,000 na cobalt-nickel da sassa na bakin karfe tun daga 2018. Kowane gudu na kasa ya koya mana wani abu: ƙimar zafin jiki fiye da lokacin riƙewa ga AMS 5387 nozzles; Tsaftar yanayi yana sa ko karya T800 alloy plug mutunci; da kuma yankin tanderu yana tasiri kai tsaye da kwanciyar hankali a cikin gidaje na famfo na piston. Waɗannan ba abubuwan lura da litattafan karatu ba ne—darussa ne daga layukan samarwa na gaske waɗanda ke sarrafa bawul ɗin ruwa da aka ƙididdige su zuwa 420 MPa da winch center shaft rollers wanda aka fallasa ga lalatawar gishiri na sa'o'i 1,500+.
Sintering na al'ada: Har yanzu Dokin Aiki-Lokacin da Ya dace
Yawancin abokan ciniki suna ɗauka na al'ada yana nufin "kawai zafi shi cikin iska." Ba daidai ba. A cikin tanderun da suka dace da ISO, ɓangarorin al'ada yana nufin daidaitaccen iko na masu canji guda uku: ƙimar dumama (yawanci 3-5 ° C / min), matsakaicin zafin jiki (1120-1280 ° C don bakin karfe, 1320-1380 ° C don alloys cobalt), da lokacin zama (minti 30-90). Muna amfani da endothermic gas (N₂-H₂ mix) ga bakin sassa da kuma high-tsarki argon ga T800 da AMS 5387-saboda ko da 20 ppm oxygen sa surface hadawan abu da iskar shaka da cewa ruguza matsa lamba bawul sealing saman. Wannan hanyar tana ba da 92-95% ƙima mai yawa. Yana da tsada kuma mai maimaitawa-amma ba don sassan da ke buƙatar> 97% yawa ko hadadden geometries tare da bangon bakin ciki ba. Mun ƙi wannan hanyar don nozzles na cobalt gami da buƙatun sifilin porosity na ciki a mahimman hanyoyin kwarara.
Sintering-Taimakawa Matsi: Yawa ba tare da Rangwame ba
Lokacin da abokan ciniki ke buƙatar kusan cikakkar yawa ba tare da mashin ɗin bayan-sinter ba, muna canzawa zuwa hanyoyin taimakon matsin lamba. Hot Isostatic Pressing (HIP) yana shafi 100-200 MPa argon matsa lamba daidai lokacin da dumama-damfara raƙuman ramukan rufe. Muna amfani da HIP akan kowane gidan famfo na AMS 5387 wanda aka ƙaddara don sabis na mai & iskar gas. Sakamakon? 99.8% yawa, 15% mafi girma gajiya rayuwa, da kuma kawar da micro-shrinkage lahani wanda ke haifar da yayyo da wuri a cikin aikace-aikacen sake zagayowar. Spark Plasma Sintering (SPS) yana aiki daban-daban: pulsed DC halin yanzu yana wucewa kai tsaye ta cikin ƙaramin foda, yana ba da damar dumama mai sauri (har zuwa 1000 ° C / min) da ƙananan lokacin sake zagayowar. Muna tura SPS don samfuri na T800 waɗanda ba daidaitattun abubuwan da ba daidai ba inda lissafin lissafi ke hana dumama HIP iri-iri-kamar tushe mai asymmetrical famfo tare da haɗaɗɗun saƙon hawa. Dukansu hanyoyin sun kai 2.3-3.7 × fiye da ɓangarorin al'ada-amma yanke 68% akan sassan abin hawa na injiniyoyi masu kayatarwa.
Bambance-bambancen Sarrafa Yanayi: Inda Chemistry ya Haɗu da Geometry
Halin yanayi ba kawai game da hana iskar shaka ba - yana shiga rayayye a cikin sintering. A cikin sintering na hydrogen, H₂ yana rage oxides na saman kuma yana haɓaka yaduwar ƙasa. Muna amfani da shi don simintin gyare-gyaren ƙarfe na buƙatar ƙarfin maganadisu a cikin nau'ikan solenoid na hydraulic. Vacuum sintering yana kawar da duk iskar gas mai amsawa amma yana buƙatar tsaftataccen foda - duk wani mai saura yana canzawa da ƙarfi, yana haifar da kumburi. Muna tanadin vacuum don matosai na cobalt inda ɗaukar carbon daga yanayin tushen nitrogen zai lalata juriya mai zafi mai zafi. Don tushen famfo bakin karfe da aka fallasa ga mahallin chloride, muna ƙara 5% hydrogen mai sarrafawa zuwa nitrogen don cimma ingantacciyar raguwar Cr₂O₃ ba tare da embrittlement ba. Kuskure rabon? Mun ga asarar 0.3% a cikin ƙarfin yawan amfanin ƙasa-kuma mun ƙi 172 kg na abu a cikin tsari ɗaya.
Me Yasa Zabinku Yake Canza Komai — Bayan Yawa
Matsaloli masu yawa-amma shine kawai wurin bincike na farko. Hanyar sintiri tana nuna tsarin hatsi, rarraba lokaci, da saura damuwa. Sintering na al'ada na bakin karfe 17-4PH yana haifar da ƙananan hatsi waɗanda ke iyakance juriyar gajiya a cikin bawul ɗin matsa lamba. Ƙirƙirar ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun HIP suna isar da mafi kyawun hatsi iri ɗaya - haɓaka rayuwar sabis ta 4.2 × a cikin gwaji na filin. Ƙarshen saman yana canzawa kuma: sassan HIP suna buƙatar 30% ƙasa da niƙa na ƙarshe don buga Ra ≤0.4 µm akan fuskokin rufewa. Matsakaicin iko ya bambanta da gaske-sintering na al'ada yana raguwa 12-15% na layi; HIP yana raguwa kawai 0.8-1.3%, yana barin mu riƙe ± 0.02 mm akan gidajen silinda mai diamita 280-mm ba tare da injin na biyu ba. Kuma tarihin zafin jiki yana rinjayar machinability: T800 sintered al'ada inji a 18 m / min; T800 da aka yi wa HIP yana buƙatar ƙimar ciyarwar 8 m/min da abubuwan saka carbide na musamman. Muna taswirar waɗannan ɓangarorin kasuwanci yayin nazarin aikin injiniya-ba bayan binciken labarin farko ba.
Fahimta iri sintering a foda metallurgy factory Ayyuka sun raba samfurori na aiki daga sassan samarwa masu mahimmancin manufa. A QINGDAO QIANGSENYUAN TECHNOLOGY CO., LTD., mun dace da dabarun daidaitawa zuwa aikace-aikacen kimiyyar lissafi-ba kawai bayanan bayanai ba. Na'urar matsa lamba na hydraulic suna samun HIP. Simintin ƙarfe mai girma yana samun hydrogen sintering. Cobalt alloy nozzles yana buƙatar sifili porosity samun SPS. Zaɓin da ya dace yana farawa da yanayin gazawar ɓangarenku-ba kasafin kuɗin ku ba. Muna inganta kowane yanke shawara game da zagayowar damuwa na zahiri, fallasa lalata, da jurewar taro. Domin a cikin madaidaicin sassan masana'antu, sintering ba mataki ba ne. Yana da tushe.
