Bincike don Juriya na Lalata na Rufin Galvalume mai zafi

Hot-tsoma Zn55Al1.6Si galvalume coatings da aka yadu amfani a da yawa filayen kamar mota masana'antu, shipbuilding, inji masana'antu da dai sauransu, ba wai kawai ta mafi anti-lalata yi fiye da na Zinc shafi, amma kuma zuwa ga low cost (da Farashin Al ya yi ƙasa da na Zn a halin yanzu). Kasashe marasa ƙarfi kamar La na iya hana haɓakar sikelin da haɓaka mannewa sikelin, don haka an yi amfani da su don kare ƙarfe da sauran su. karfe gami da hadawan abu da iskar shaka da lalata. Duk da haka, akwai ƴan littattafai kaɗan da aka buga akan aikace-aikacen La a cikin murfin galvalume mai zafi mai zafi, kuma a cikin wannan takarda an bincika tasirin ƙarar La akan juriya na lalata na galvalume mai zafi.

Gwaji

[1] Tsatsa mai zafi

Zafin da aka tsoma Zn-Al-Si-La gami da 0,0.02wt.%, 0.05wt.%, 0.1wt.% da 0.2wt.% La an yi amfani da su akan Ф 1 mm m karfe waya. Tsarin ya kasance kamar haka: tsaftacewa don cire tsatsa da mai ta hanyar babban igiyar ruwa (55 ° C) → tsaftacewa ta ruwa → ruwa (85 ° C) → bushewa (100 ~ 200 ° C) zafi- tsoma (640 ~ 670 °C, 3 zuwa 5).

[2] Gwajin rage kiba

Gwajin asarar nauyi an auna ta ta hanyar gwajin feshin gishiri na jan karfe-accelerated acetic acid (CASS) da gwaje-gwajen lalata da aka gudanar a cikin dakin feshin gishiri da 3.5% NaCl bayani. Bayan gwaje-gwajen, an cire kayan da aka lalata ta hanyar injina, an wanke su da ruwa mai gudu, sannan a bushe da iska mai sanyi da asarar nauyi ta hanyar sikelin lantarki. A cikin lokuta biyu, uku paralAn yi samfuran lel don samun ƙarin madaidaicin sakamako. Lokacin gwaji shine 120h don gwajin CASS da 840h don gwajin nutsewa.

[3] Gwajin Electrochemical

Electrochemical gwajin da aka gudanar ta hanyar IM6e electrochemical aiki tashar kawota ta Jamus, shan platinum farantin a matsayin counter electrode, cikakken calomel electrode a matsayin tunani lantarki, da zafi tsoma Zn-Al-Si-La coatings m karfe waya a matsayin aiki lantarki. Matsakaicin lalata shine 3.5% NaCl bayani. Wurin da aka fallasa ga maganin gwajin shine 1cm2. Electrochemical impedance spectroscopy (EIS) ma'auni da aka za'ayi tare da mitar kewayon tafi daga 10 kHz har zuwa 10 mHz, nisa na sinusoidal ƙarfin lantarki siginar ya kasance 10 mV (rms) .Raunan polarization masu lankwasa an rubuta a cikin ƙarfin lantarki kewayon daga -70 mV. zuwa 70mV, ƙimar binciken shine 1 mV/s. A cikin duka biyun, gwaji bai fara ba har sai yuwuwar lalata ta kasance barga (bambancin ƙasa da 5 mV a cikin 5 min).

[4] Nazarin SEM da XRD

SSX-550 scanning electron microscope (SEM) ne yayi nazarin yanayin halittar saman samfuran bayan gwaje-gwajen lalata a cikin ɗakin feshin gishiri da 3.5% NaCl bayani. Abubuwan lalata da aka kafa akan saman samfuran a cikin gishirin gishiri da 3.5% NaCl bayani an gwada su ta amfani da PW-3040160 X-ray diffraction (XRD).

Sakamako da tattaunawa

[1] Juriya na lalata
[1.1] Rage nauyi
Fig.1 yana kwatanta sakamakon gwajin asarar nauyi a cikin majalisar feshin gishiri da 3.5% NaCl bayani. Adadin lalata samfuran a cikin duka biyun ya ragu da farko tare da haɓaka abun ciki na La har zuwa 0.05wt.% sannan ya ƙaru tare da ƙara haɓaka abun cikin La. Sabili da haka, an sami mafi kyawun juriya na lalata a cikin suturar da ke ɗauke da 0.05wt.% La. An gano cewa a lokacin da nutsewa gwajin, ja tsatsa da aka samu da farko a kan 0wt.% La shafi surface a 3.5% NaCl bayani, duk da haka, har sai da immersion gwajin ƙare, babu ja tsatsa a kan 0.05wt.% La shafi surface. .

2.1.2 Gwajin Electrochemical

Hoto 2 yana nuna raunin polarization mai rauni don suturar alloy na Zn-Al-Si-La a cikin 3.5% NaCl bayani. Ana iya ganin cewa siffar raunin polarization mai rauni ya nuna 'yan bambance-bambance, kuma tsarin lalata na kowane nau'i na kayan haɗin gwal yana sarrafawa ta hanyar cathodic dauki. Sakamakon dacewa na Tafel dangane da raunin polarization mai rauni a cikin Fig.2 an gabatar da su a cikin Table 1. Kamar yadda aka kwatanta da gwajin asarar nauyi, an kuma gano cewa za a iya inganta juriya na lalata na galvalume ta hanyar ƙarami na La da ƙananan ƙananan. An sami ƙimar lalata da 0.05wt.% La.

Fig.3 yana wakiltar zane-zane na Nyquist da aka rubuta don sutura tare da nau'i daban-daban na La ƙari da aka fallasa zuwa 3.5% NaCl bayani na 0.5 h. A kowane hali, akwai nau'i biyu na arcs wanda ke nufin sau biyu. Wanda ke bayyana a babban mitar yana wakiltar sifar dielectric na murfin gami, yayin da wanda ke ƙasan mitar ya yi daidai da na ƙaramin ƙarfe mai laushi a cikin pores (watau lahani mai rufi). Yayin da ƙari na La ya karu, diamita na babban mitar arc ya karu, wannan tasirin ya fi bayyana a cikin yanayin Zn55Al1.6Si0.05La alloy shafi. Tare da ƙara haɓaka abun ciki na La, duk da haka, diamita na babban mitar baka ya ragu da sabani. A halin yanzu, tsakiyar dukkanin arcs sun jingina zuwa hudu na hudu, yana nuna cewa tasirin watsawa ya faru a kan farfajiyar lantarki. A karkashin wannan yanayin, ana iya samun sakamako mafi kyau ta hanyar amfani da CPE (m lokaci kashi) maimakon capacitance mai tsabta wanda aka nuna ta hanyar amfani da CPE. sauran kungiyoyin bincike.