Solid Solution Hardening of Nickel —Role of Transition Metal and B-subgroup Solutes—

Abstract

A systematic investigation is made on the solid solution hardening of binary nickel alloys with additions of B-subgroup and transition metal elements. The 0.2% flow stress at 77 K and the Young's modulus are measured for a variety of binary alloys to evaluate the rate of solution hardening per one available data on the rate of change in lattice constant (da/dc), interpretation of the solution hardening that the hardening is more intense by the additions of transition metal elements than by the additions of B-subgroup elements where the hardening is linearly related with a combined parameter for the interaction between solute atoms and edge dislocations. Then the necessity is raised to carry out the similar type of investigation on the solution hardening of nickel in order to clarify whether the anomalous hardening effect is inherent in the Ll2 crystal structure of Ni3Al or in the majority component of nickel.Technological interest in nickel alloys has often centered on improving the heat resistant properties such as high temperature strength and creep strength by making alloys multicomponent. For this purpose, the additions of transition metals are generally accepted. Prominent examples are the modifications of commercial superalloys, in which the additions of those elements have been properly chosen utilizing regression analyses. As a more fundamental approach, the solid solution hardening has been studied in nickel binary alloys by a number of workers (2)- (9), however, the alloy

Evaluation of Solid-Solution Hardening in Several Binary Alloy Systems Using Diffusion Couples Combined with Nanoindentation

“…pct 2/3 (see Figure S2 in Supplementary Material)-taking into account of the large scatter in the data, this value compares well with that obtained in the present study. In addition, these results are qualitatively consistent with the compressive flow stress data of Mishima et al [31] In Reference 31 the flow stress of~100 MPa of pure Ni was retained on addition of~2 at. pct Fe and increased to~150 MPa for an 8 at.…”

“…These are in qualitative agreement with the experimental results. The observed SSH is also in good agreement with the literature [9,[31][32][33] on macroscopic mechanical testing. The k values of 411 and 11 MPa/at.…”

“…A similar behavior was found by Mishima et al [31] with Mo, Ta, Nb, and Zr exhibiting a positive deviation from the linear fit to Ni binary solid-solution data (obtained from macroscopic testing). The deviation was attributed to contributions from electronic effects in transition metal solid-solutions.…”

“…The deviation was attributed to contributions from electronic effects in transition metal solid-solutions. [31,39] Also, solvent-solute combinations with a large difference in valence electrons are found to have a greater effect on SFE, [29] and the occurrence of SFs is found to be more pronounced in alloys with larger atomic number difference. [35] Thus, an additional contribution over the elastic effects, leading to higher values of k, can be expected.…”

The Effect of Solute Elements on Hardness and Grain Size in Platinum Based Binary Alloys

“…Suzuki's group studied solid solution hardening in Ni-X binary alloys and Ni-40 at%Co-X ternary alloys, reporting that solid solution hardening in alloys with the solubility limit became larger than that of alloys with a completely miscible similarly to the present result. [17][18][19] It was also reported that an extra hardening observed in the former type of alloys increased with a reduction of the solubility limit. Thus, in the present Pt-based binary alloys, the relationship between the increment in hardness and an inverse of the solubility limit in a respective alloy was investigated, of which result is in Fig. 14.…”