Atomistic Simulations and Experimental Investigations of the Diffusion Behavior of Steel/ZCuPb20Sn5 Bimetals

Mingjie Wang,Guowei Zhang,Hong Xu,Yufei Zhang

doi:10.3390/coatings10060549

Abstract

A hybrid verification method consisting of experiments and molecular dynamics simulations was implemented to investigate the diffusion behaviour of steel/ZCuPb20Sn5 bimetals. The effects of different carbon steels (Q235 steel, 45 steel, and T8 steel), pouring temperatures, and holding times on their microstructures and mechanical properties were studied to obtain the optimum process parameters. The experimental results indicated that the pouring temperature and holding time played an imperative role in improving the shear strength of the steel/copper bimetallic composite. The highest bonding strength of all the steel/copper bimetallic composites was obtained at 1523 K and the holding time of 40 min. Moreover, the carbon steel of 45 steel with a ZCuPb20Sn5 interface exhibited the highest bonding strength because of the appropriate pearlite content along with the preferable structure and micro-hardness for the considered diffusion width and bonding strength. Meanwhile, the diffusion distance of copper atoms in the carbon steel matrix was smaller than that of iron atoms in the ZCuPb20Sn5 matrix. In the simulation results, the diffusion coefficient of Cu atoms was smaller than that of Fe atoms, but the diffusion distance of Fe atoms in the Cu bulk was larger than that of Cu atoms in the Fe bulk; this showed a significant agreement with the experimental result.

Highlights

Bimetallic-bonding compound materials join two types of metals by using different methods [1,2]which combine the excellent performance of the metals used and considerably improve the properties of strength, hardness, and wear resistance [3,4]
The embedded atomic method (EAM) potential developed by Bonny et al [36], which has far been used for exploring diffusion properties, was used for modelling the atomic interaction of Fe–Cu bimetallic atoms [37] and the mechanical properties [38] of Fe–Cu alloys
The above figure of the diffusion the diffusion distance of the steel/copper composite decreased with an increase in the pearlite. All these distance shows that the diffusion distance of the steel/copper composite decreased with an increase in the pearlite. All these results indicated that the diffusion interface of the steel/copper was the result of the diffusion distance and the interface structure of the steel/copper bimetal composite

Summary

Introduction

Bimetallic-bonding compound materials join two types of metals by using different methods [1,2]which combine the excellent performance of the metals used and considerably improve the properties of strength, hardness, and wear resistance [3,4]. As one of the best engineering materials, iron–copper bimetals play an important role in many industries [5,6], in aerospace and pump construction, because of their high bonding strength and good wear resistance [7,8]. There are many methods to fabricate copper/steel bimetals, such as explode welding [11], friction welding [12,13], laser welding [14,15], powder metallurgy [16,17,18], squeeze casting [19], induction cladding [20,21], and transient liquid phase [22,23,24]. Welding and induction cladding are used conventionally They are mainly applied in components with a regular interface, and it is difficult to produce complex bimetallic components with an inner cavity.

Methods

Results

Discussion

Conclusion