# TaMoNbTiZr Multielement Alloy for Medical Instruments

## TL;DR

A new biocompatible TaMoNbTiZr alloy was developed for medical instruments, showing improved hardness and compatibility with human cells.

## Contribution

The development of a novel TaMoNbTiZr multielement alloy with enhanced hardness and biocompatibility for medical applications.

## Key findings

- The alloy's hardness increased by over 40% after heat treatment.
- The alloy showed good biocompatibility with mesenchymal stem cells and fibroblasts.
- Cytolysis effects were minimal, indicating low toxicity.

## Abstract

In this paper, a new TaMoNbTiZr multielement alloy has been designed, using chemical elements that exhibit extremely low bio-toxicity for the human body. The alloy was obtained by melting in vacuum arc remelting (VAR) equipment MRF ABJ 900 from high-purity chemical elements (99.5%) as mini-ingots having about 40 g weight each. The biocompatible alloys underwent changes in hardness after performing the annealing at 900 °C for 2 h, followed by cooling in water. The new alloy had an average hardness in the cast state of 545 HV0.5, and after heat treatment, it hardened to a value of 984 HV0.5, over 40% higher than that in the casting state, which ensures a longer working period. To use them as materials for medical instruments, their biocompatibility was highlighted through specific laboratory tests. For this, mesenchymal stem cells isolated from bone tissue and a human fibroblast cell line were cultured in vitro on the TaMoNbTiZr alloy’s surface. The biocompatibility of the alloy with the biological environment was evaluated by analyzing cell viability, adhesion, and proliferation, and in parallel, the cytolysis effects manifested by the increase in lactate dehydrogenase activity in the culture media were analyzed.