Mechanical Properties of the MG-Based Amorphous/Nano Zirconia Composite Alloy

Abstract

Mg-based composites are fabricated through mechanical alloying (MA) the Mg65Cu20Y10Ag5 amorphous alloy spun and mixed with 1-5 vol.% spherical nano-sized ZrO2 particles in the planetary mill, after then formed by hot pressing in Ar atmosphere under different pressures at the temperature 5 K above the glass transition temperature (Tg). The microstructure characterizations of the resulting specimens are conducted by means of XRD, FEG-SEM, and TEM techniques. It is found that the nano-sized ZrO2 dispersed Mg-based composite alloy powders can reach to a homogeneous size distribution (about 80 nm) after 50-hour mechanical alloying. After hot pressing of these composite alloy powders under the pressure of 1100 MPa at 409K, a 96% dense bulk specimen can be formed. Throughout the MA and hot pressing, the amorphous nature of the Mg65Cu25Y10Ag5 matrix is maintained. The hardness of the formed bulk Mg-based composites (with 3 vol.% nano-sized ZrO2 particles) can reach to 370 in Hv scale. In addition, the toughness of the formed bulk Mg-based composites presents an increasing trend with the content of nano-sized ZrO2 particles and can reach to 8.9 MPa m .

Recent progress in metallic glasses in Taiwan

“…In addition, the hot-pressed composite can reach a 96% density, 360 in H v hardness, and 700 MPa for the compressive strength. Moreover, the toughness of the Mg based BMGCs exhibit an increasing trend with increasing nano-sized ZrO 2 content, and can reach a level of 8.9 MPa m 0.5 [32,33].…”

“…liquid region 57-61 K. This Ni-Ta-Sn BMG shows high hardness, typically H v w 1000, and a compressive fracture strength 856-1192 MPa. The Ni 58 Ta 36 Sn 6 BMG also exhibits good corrosion resistance in the anodic region[30].The synthesis and characteristics of the Mg based BMG composites (BMGCs) have been studied in I-Shou University[31][32][33][34][35]. The Mg based BMGCs are fabricated through mechanical alloying (MA) in the planetary mill, using amorphous Mg 65 Cu 25Àx Y 10 Ag x (a) The stacked Zr and Ti foils after 50 ARB cycles, (b) typical TEM micrograph and electron diffraction pattern of the vitrified Zr 50 Ti 50 region by ARB, and (c) typical XRD patterns of the ARB Zr 50 Ti 50 samples after different cycles at room temperature[49].…”

Pengaruh Variasi Tekanan Hot Press pada Kekuatan Biokomposit Biji Salak - Polipropilena

“…Penurunan ketebalan ini dapat dipahami karena efek tekanan mereduksi jarak antara partikel serta mendekatkan kontak filler dengan matriks bahkan mengurangi porositas sehingga meningkatkan density. [14] Tekanan hot press pada ketebalan memiliki pengaruh tidak sebesar efek perubahan komposisi Gambar 3. Grafik perbandingan tebal sampel vs komposisi dan tekanan hot press Dari perhitungan gramasi sampel, diperoleh data gramasi seperti ditunjukkan oleh gambar 4 (tebal sampel diperhitungkan sama, yaitu 1,6 mm).…”

“…Tekanan hot press dapat mendekatkan jarak antar partikel filler sehingga terjadi peningkatan interaksi antara matriks dengan filler dan menyebabkan ukuran pori pada komposit menjadi lebih kecil dan sedikit. [14] Dari penelitian terdahulu menunjukkan potensi biji salak sebagai partikel penguat yang dapat menghasilkan kekuatan komposit yang setara dengan bahan alam lainnya. Biji salak dipilih karena terinspirasi dari penelitian menggunakan biji buah cherry, dimana keduanya memiliki karakteristik kekerasan yang mirip.…”