Microstructural Evolution of the Hot Rolling Interface in 304 Stainless Steel/Q235 Carbon Steel Clad Plates for Mi-crophone Pop Filters

Bin Sun

DOI: https://doi.org/10.64486/m.65.4.4
Online publication date: March 3, 2026

Abstract: In response to the comprehensive requirements of microphone pop filters for materials’ corrosion resistance and structural stability, 304 stainless steel/Q235 car-bon steel clad plates have emerged as the preferred choice due to their superior performance and the hot rolling process is crucial to ensuring the bonding quality of the interface. Taking this clad plate as the research object, this study systematically investigates the influence laws of the hot rolling process on the evolution of interface microstructure and bonding characteristics by comparing annealed samples with double hot-rolled ones. The results indicate that a sound metallurgical bond is formed between the 304 layer and the Q235 layer, with the micro-structures on both sides of the interface being austenite and ferrite + pearlite, respectively; a ferrite decarburized layer with a thickness of approximately 140 μm forms on the Q235 side. After double hot rolling, the grains of the clad plate are significantly refined.

Keywords: hot rolling process; 304 stainless steel; Q235 carbon steel; interface microstructure; microphone pop filter

This article is published online first and will appear in Metalurgija, Vol. 65, Issue 4 (2026).