Structure and properties of powder alloys Fe–(45-15)%Ni–(10-5)%Cu, obtained via mechanical alloying

Abstract

The article investigates the structure and properties of %Ni-(10-5)%Cu powder alloys. The production method included low-and high-energy (mechanical alloying, МА) treatment of Fe, Ni, and Cu powders in a planetary ball mills followed by hot-pressing of mixes at 950 °С. After MA, the mixtures consist of composite granules with a lamellar structure and particle size of 10-100 µm. After low-energy treatment, three phases were detected by XRD in hot-pressed samples: α-Fe-based solid solution BCC-(Fe, Ni, Cu), Ni-based solid solution FCC-(Ni, Fe, Cu), and FCC-FeO. The appearance of FeO is caused by the partial oxidation of iron during mixing and hot pressing. The total oxide content does not exceed 1.3 wt%. For Fe-X% Ni-5% Cu alloys the ultimate bending strength depends on the nickel content (X, %) linearly according to the equation s ben = −19⋅X + 1995 [MPa], where 15 % ≤ X ≤45 %. Alloys obtained by MA have a homogeneous structure and depending on the composition can be either two-or three-phase. As a result of MA the hardness of the alloys increased by 20-21 HRB, and the ultimate bending strength increases by 300-540 MPa. The alloy with the composition 80%Fe-15%Ni-5%Cu has the maximum bending strength s ben = 2135 ± 60 MPa. The wear of MA alloys is (4.1-4.4)⋅10 −5 mm 3 /(N⋅m) which is more than two times lower than the wear of alloys obtained by low-energy treatment.

Mechanical properties and wear resistance of Fe–Ni–Cu-based metal matrix composites reinforced with hollow corundum microspheres

“…Зеренная структура генерировалась с использованием тесселяции Пуассона-Вороного [24]. По результатам исследования микроструктуры композитов на основе сплава Fe-Ni-Cu [25] была построена двухуровневая модель. Модель первого уровня (макромодель) включала в себя зерна размером от 350 нм до 12 мкм, разделенные прослойками зернограничной фазы шириной 70~100 нм, а также контролирующие износостойкость добавки (рис.…”