Study of Mechanical Properties of Fe-ni-co Alloy With Alloying Elements Used in Space Telescopes.

Abstract

One of the main purposes of modern metallurgy is to improve the properties of existing materials and develop fundamentally new materials. Improving the efficiency of space telescope constructions is always an urgent task for the space industry. Reducing weight, maintaining ductility and improving operational performances are the aims that materials scientists will always face. Invar Fe-Ni-Co alloy is widely used in many industries requiring high dimensional stability such as metrology, high precision instrumentation, and optical assembly in the space industry. Hypothesis: the addition of certain chemical elements will improve the mechanical properties and expand the scope of the developed alloy. In this work, the following purpose is set: to investigate the operational properties of the Fe-Ni-Co alloy with alloying elements used in high-precision technologies. In this work, experiments for microhardness, a research on microstructure, determination of the Coefficient of Linear Thermal Expansion (CLTE) were carried out. In the course of the work, Fe-Ni-Co was smelted with the addition of alloying elements in the form of Cr, Mn. In the initial state, the microhardness of the alloy was Нμ = 6433 MPa. The highest microhardness index was achieved after annealing at 7000C (5 hours) Нμ = 9393 MPa, which is 46% higher than the initial one. Novelty of work: We have developed a new alloy with improved mechanical properties, which can replace invar, and subsequently contribute to a sharp push in the sphere of astronomy. Results of exploration: We recommend using the results of this work in the manufacture of parts for space telescopes that require resistance to thermal vibrations and aggressive surroundings. The CLTE measurements of the alloys were carried out at room temperature under standard conditions. At 2000C, the sample expanded by 0.006 mm, which corresponds to an CLTE of α=1.8×10-6К-1.