ALUMINIUM MATRIX CAST COMPOSITE (AMCC) WITH HYBRID REINFORCEMENT

8/15 Archives f Fundry, Year 2005, Vlume 5, 15 Archiwum Odlewnictwa, Rk 2005, Rcznik 5, Nr 15 PAN Katwice PL ISSN 1642-5308 ALUMINIUM MATRIX CAST COMPOSITE (AMCC) WITH HYBRID REINFORCEMENT A. DOLATA-GROSZ 1, J. ŚLEZIONA 2, B. FORMANEK 3, 1,2 Deartment f Allys and Cmsite Materials Technlgy, 3 Deartment f Material Science Silesian University f Technlgy, Faculty f Materials Science and Metallurgy, Str. Krasińskieg 8, PL-40-019 Katwice, Pland ABSTRACT The rcess f rducing and the structure f aluminium matrix cast cmsites with cmsite wders cntaining chrmium and titanium carides has een resented in the article. The reinfrcing hases were tained y means f NiCr- Cr 3 C 2 -TiC wder mixtures frmed during self-ragating high-temerature synthesis rcess. A cmsite ally was rduced y casting methds (mechanical mixing and centrifugal casting) after which its structure was determined. The designed rcess allws fr the structure mdificatin f the alied cas ting aluminium allys in different technlgical variants. Key wrds: aluminium ally, intermetallic and ceramic hases, casting methds structure. 1. INTRODUCTION Amng the methds f in situ cmsites rductin the wder metallurgy and casting technlgies are used [1-12]. By casting methds, Al, Ti, Cu, NiAl r TiAl ased cmsites can e tained with disersin articles: TiC, TaC, ZrC, B 4 C, SiC TiB 2, Si 3 N 4, AlN, BN, and Al 2 O 3, whse size, deending n the rductin technlgy, ranges etween 0.1 and a dzen r s m, with a vlume fractin f 5 55%. In the literature data, there are nly sme signals aut aluminium cmsites cntaining 1 dr inż., agrsz@lsl.katwice.l, 2 rf. dr ha. inż., slezina@lsl.katwice.l 3 dr inż., frman@lsl.katwice.l

71 caride hases different than silicn caride, aluminium caride r titanium caride [1-3,5,13-16]. There is n infrmatin, hwever, aut the rductin and alicatin f tw caride hases fr hyrid reinfrcement f aluminium allys. It has een assumed in wn investigatins that chrmium and titanium carides, due t their hysicchemical rerties, can frm effective reinfrcement in cmsite aluminium allys, in articular thse intended fr centrifugal casting f rducts. The Cr 3 C 2 chrmium caride with a NiCr matrix in the frm f wder is mst ften used fr lasma r suersnic sraying f catings f high wear resistance, e.g. arasive r ersin resistance at amient and elevated temeratures [11,12,17,18]. Chrmium caride catings are intended fr use in wer installatins u t a temerature f 800 0 C. Titanium caride, which has higher micrhardness (32HV µ ) cmared t the chrmium caride Cr 3 C 2 (13HV µ ), shuld enhance the trilgical rerties f rducts. The alicatin f a cmsite NiCr/Cr 3 C 2 -TiC wder fr the mdificatin f the Al-Mg ally is the suject matter f the technlgical and structural investigatins resented in this aer. It was assumed that due t the difference in the density f chrmium and titanium caride hases, it wuld e ssile t frm casts with a layered structure and hyrid reinfrcement [9]. The cntent f a slid slutin NiCr 80/20 in the chemical cmsitin f a cmsite wder shuld underg disslutin in an aluminium ally, where an additinal, disersin reinfrcement frm Al-Ni r Ni-Cr-Al intermetallic hases will e frmed [19]. The final structure f the cast will e als influenced y staility f the caride hases in the disslved Al-Mg ally. 2. PURPOSE AND SCOPE OF RESEARCH The gal and sce f the research has een determined ased n literature data, wn investigatins and the assumtins made. T accmlish the rincial urse f the research were determinatin f the alicatin ssiility f cmsite wders intended fr thermal sraying rcesses fr the mdificatin f aluminium casts. The rincial urse f the research was t determine the technlgical cnditins and arameters f the rductin f an aluminium matrix cast cmsite with chrmium and titanium carides. It was assumed that the lanned research cycle shuld rvide infrmatin whether: - carides included in the chemical cmsitin f a cmsite wder retain their mrhlgy and hase cmsitin during the rcess f liquid aluminium mixing, and susequent remelting and centrifugal casting; - agglmerates f the cmsite NiCr/Cr 3 C 2 -TiC wder underg artial sluilizatin and hase transitin t hases with aluminium share; - cmsite wders intrduced int a liquid ally f aluminium with magnesium are wetted;

Intensity 72 - the incrratin f cmsite wders cntaining carides f high density will allw the frmatin f an external layer f the cast with an increased amunt f reinfrcing hases. The sce f the research included: - determinatin f the structure and hase cmsitin f a wder with chrmium and titanium carides, - faricatin f a cmsite with an aluminium matrix and carides - determinatin f the structure and hase cmsitin f the cmsite, - faricatin, in a centrifugal casting rcess, f a cmsite with a layered distriutin f reinfrcing hases and determinatin f its structure. 3. EXPERIMENTAL MATERIALS AND METHODS As the matrix material fr the rduced cmsites, a casting ally f aluminium and magnesium, AlMg10 (AG10), was used. A cmsite wder cntaining chrmium and titanium carides as well as a hase f slid slutin NiCr (NiCr/Cr 3 C 2 -TiC) were used t frm the cmsites. The cmsite wder was tained in the self-ragating high-temerature synthesis (SHS) [11,12]. The hase cmsitin and structure f the wder used fr the mdificatin f the matrix ally are shwn in Figure 1. 100,0 90,0 80,0 70,0 60,0 50,0 40,0 30,0 20,0 10,0 a Cr3C2 TiC Cr Ni Cr 3 C 2 TiC NiC 0,0 10 15 20 25 30 35 40 45 theta Fig. 1. Diffractin attern a) and the structure ) f NiCr-Cr 3 C 2 -TiC wder mixture used fr the matrix ally mdificatin, the wder surface, lished sectin, SEM. Rys. 1. Dyfraktgram a) i struktura mieszaniny rszków NiCr- Cr 3 C 2 -TiC użytej d mdyfikacji stu snwy, wierzchnia rszku, zgład, SEM The cmsite wder, 20-40µm in size, was incrrated int mechanically mixed liquid aluminium in the range f temeratures frm 720 0 C t 740 0 C [9]. Thus tained cmsite susensin was sujected t mixing fr 10 minutes and then cast

Intensity 73 int a grahite muld. By this methd, casts f a different cmsite wder vlume fractin were frmed: 15, 7.5 and 5%, resectively. Material fr structural investigatins was samled frm the cmsites tained. Next, cmsite ingts were remelted and cast int a rtating muld in rder t tain centrifugal casts [13,14]. The structure f the wders and cmsite casts was analyzed using tical and scanning micrscy as well as an X-ray hase analysis. 4. THE RESEARCH RESULTS The hase cmsitin and the heterhase structure f the cast tained as a result f incrrating the cmsite NiCr-Cr 3 C 2 -TiC wder int the AlMg10 ally are resented in Figure 2. a 2500 2000 1500 1000 500 Al AlNi Al 5 Cr Al 2 Cr x Al 9 Cr 4 Cr 3 Ni TiC x x x x x x x 0 20 30 40 50 2Theta 60 70 80 90 Al 5 Cr TiC c TiAl 80µm Al 20µm Fig. 2. The diffractin attern a) and the structure f aluminium cast cmsite with hyrid reinfrcement after grvitatinal casting, OM, ), c). Rys. 2. Dyfraktgram a) i struktura kmzytu aluminiweg ze zrjeniem hyrydwym dlewaneg grawitacyjnie, MŚ, ), c).

Intensity 74 Based n structural investigatins and X-ray analysis, resence f hases f varied disersin, mrhlgy and chemical cmsitin in the aluminium matrix was crrrated (Fig. 2,3). 4000 3000 Al AlNi Al 5 Cr 2000 Al 4 C 3 TiC A 1000 0 1 301 601 901 1201 Theta Fig. 3. The diffractin attern a) and the structure f aluminium cast cmsite with hyrid reinfrcement after grvitatinal casting, SEM, ), c). Rys. 3. Dyfraktgram a) i struktura kmzytu aluminiweg ze zrjeniem hyrydwym dlewaneg grawitacyjnie, SEM, ), c). The X-ray analysis f the hase cmsitin f the casts shws lw crrsin resistance f titanium caride in the AlMg10 ally and its transitin t a AlTi hase. The X-ray investigatins als crrrated the ccurrence f the Al 4 C 3 caride [1,5]. The reciitatins frmed in the disslutin rcess, larger than the chrmium caride grain in the cmsite wder, are hases f Al 5 Cr and Al 2 Cr tye, whereas the inding NiCr matrix in the cmsite wder is reactive in melted aluminium, causing destructin f its shae and frmatin f NiAl hases (Figs 3,4).

75 100 µm a Fig. 4. The structure f aluminium cast with reinfrcement hases taining y the centrifugal casting: a) structure f utside layer, OM, ) macrstructure. Rys. 4. Struktura kmzytu aluminiweg z fazą zrjącą uzyskaneg rzez dlewanie dśrdkwe a) struktura warstwy zewnętrznej, MŚ, ), c). a c d Fig. 5. SEM micrgrah f aluminium cmsite with reinfrcement hases after centrifugal casting, a), c); the AlMgSi eutectic qualitative analysis, EDS, ); the AlNi eutectic qualitative analysis, EDS, d). Rys. 5. Zdjęcie SEM kmzytu aluminiweg z fazą zrjącą uzyskaneg rzez dlewanie dśrdkwe a),c); analiza jakściwa eutektyki AlMgSi, ); analiza jakściwa eutektyki AlNi.

76 5. CONCLUS IONS The investigatins carried ut have crrrated that there is a technlgical ssiility f rducing cmsite casts with aluminium matrix and hyrid reinfrcement y incrrating the NiCr-Cr 3 C 2 -TiC wder in the cmsite ally. Bearing in mind the rerties f melted aluminium cmsite and the technlgical arameters f the centrifugal casting rcess [9], it seems eneficial t rduce an ally with a 7.5% fractin f reinfrcing hases (Fig. 3,4). The AlMCs thus tained characterize with a structure f a varied disersin f hases, which were frmed as a result f carides and NiCr disslutin in the aluminium matrix. At this stage f the research, the tained results shw that it is urseful t rduce aluminium cmsites with hyrid reinfrcement y cmining the rcesses f wder metallurgy and casting methds. In the n-ging research, a crrectin f the technlgical arameters f cmsites rductin is taken int accunt and investigatins f the mechanical and trilgical rerties are erfrmed. The resented results are art f a wider research rject investigating the influence f the tye f reinfrcement and its hase cmsitin n the structure and rerties f heterhase cast cmsites with an aluminium matrix [5-9,]. REFERENCES [1] Fraś E., Janas A., Klus A., Górny M.: Synteza kmzytów in situ Al-TiC raz Cu-TiC z wykrzystaniem gazu reaktywneg, Inżynieria Materiałwa, 2000, R. 21 nr 2 s. 48-55. [2] Fraś E., Janas A., Klus A.: Odlewany kmzyt aluminiwy in situ umacniany cząstkami rków tytanu, Kmzyty (Cmsites) 1, PTMK 1(2001), s. 23-27. [3] Fraś E., Janas A., Wierziński S., Klus A.: Odlewane aluminiwe kmzyty,,in situ'', umacniane węglikami tytanu, IV Międzynardwa Knferencja Naukwa: Zaewnienie jakści w dlewnictwie 2000, Krzenięcie Metali i Stów PAN, 2000 R. 2 nr 43, s. 167-176. [4] Lakshmi S., Lu L., Guta M.: In situ rearatin f TiB 2 reinfrced Al ased cmsites, Jurnal f Materials Prcessing Technlgy 73 (1998), s. 160 166. [5] Dlata-Grsz A., Frmanek B., Ślezina J., Wieczrek J.: Aluminium hyrid Cmsites reinfrced with intermetallic and ceramic hases, Archives f Fundry, 4/2004/14,.126-131. [6] Dlata-Grsz A., Frmanek B., Ślezina J., Wieczrek J.: Al- FeAl-TiAl-Al 2 O 3 cmsite with hyrid reinfrcement, in. COMMENT 2005: 13th Int. Sc. Cn. Achievements in Materials and Mechanical Engineering AMME'2005, Jurnal f Materials Prcessing Technlgy, Elsevier, w druku. [7] Dyzia M., Ślezina J., Dlata-Grsz A., Wieczrek J.: Alicatin f Al- FeOTiO 2 System t the Prearing f In-Situ Aluminium Cmsites Reinfrced

77 with Ceramic and Intermetallic Phases, Eurean Cngress n Advanced Materials and Prcess, Eurmat 2002, Lzanna. [8] Dlata-Grsz, Józef Ślezina, Jaku Wieczrek, Blesław Frmanek: Struktura dlewów dśrdkwych w kmzytach Al-FeO TiO 2, (Cmsites), Kmzyty 4 (2004) 10, s.164-169. [9] Dlata-Grsz A., Frmanek B., Ślezina J., Wieczrek J.: Structure f heterhases aluminium cast cmsites cntained chrmium and titanium carides, Kmzyty (Cmsites) 2005, w druku. [10] Yshimi Watanae, Tatsuru Nakamura, Micrstructures and wear resistances f hyrid Al-(Al 3 TiAl 3 Ni) FGMs faricated y a centrifugal methd, Intermetallics 9 (2001), s. 33-43. [11] Frmanek B., Szymański K., Szczucka-Lasta B., Bierska B.: Kmzytwe rszki i natryskiwane cielnie włki z snwą NiCr i fazami międzymetalicznymi, Inżynieria Materiałwa, NR6 (137)/2003, s. 412-416. [12] Frmanek B., Szymański K., Szczucka-Lasta B.: Structure f cmsite wders with Ni-Cr matrix and FeAl hases, carides and aluminium xide, Kmzyty (Cmsites), nr 5, 2002, Częstchwa 2002, str. 278-282. [13] Dlata-Grsz A., Ślezina J.: Czynniki determinujące kształtwanie struktury w kmzytach Al.-cząstki ceramiczne w rcesie dlewania dśrdkweg, Inżynieria Materiałwa, Nr 6 (137)/2003, s. 613-616. [14] Dlata-Grsz A., Ślezina J., Wieczrek J., Dyzia M.: Structure and functinal quality rerties f cmsites sleeves taining y centrifugal casting, Acta Metallurgica Slvaca, 8, 2/2002, str. 283-288. [15] Pandey A.B., Mishra R.S., Mahajan Y.R.: Effect f isthermal heat treatment n the cree ehavir f an Al-TiC cmsite, Materials Science and Engineering A206 (1996), s. 270-278. [16] Velgsva O., Besterci M.: Influence f stain rate and temerature n fracture mechanism f disersin strengthened Al-12Al 4 C 3 system, Materials Letters 57 (2003), s. 4014-4017. [17] He J., Ice M., Lavernia E.J.: Synthesis and Characterizatin f Nanstructures Cr 3 C 2 -NiCr Elsevier Science, Nanstructure Materials, 1998, vl. 10, n. 8,. 1271-1283. [18] Schuster J.C.; Du Y. Thermdynamic Descritin f the System Ti-Cr-C, Calhad 1999, T. 23, nn. 3, s. 393-408. [19] Mrsi K., McShane H., McLean M.: Effect f secimen size n the cmsitin f ht extrillin reactin synthesized NiAl, Jurnal f materials Science Letters 19 (2000), s. 331-332.

78 ODLEWANY KOMPOZYT ALUMINIOWY (AMCC) Z HYBRYDOWYM UMOCNIENIEM STRESZCZENIE W artykule rzedstawin rces trzymywania i strukturę dlewanych kmzytów aluminiwych z kmzytwymi rszkami zawierającymi heterfazwe umcnienie w staci węglika chrmu i tytanu. Fazy zrjące trzyman stsując mieszaninę rszków kmzytwych tyu NiCr-Cr 3 C 2 -TiC uzyskaną w rcesie samrzwijającej się syntezy wysktemeraturwej (SHS). Sty kmzytwe wytwrzn metdami dlewniczymi (mechaniczneg mieszania i dlewania dśrdkweg) i rzeadan ich strukturę. Oracwany rces wytwarzania kmzytów zwala w różnych wariantach technlgicznych na mdyfikację struktury stswanych dlewniczych stów aluminium. Recenzwał Prf. Zigniew Knka