Influence of transient temperature on liquid metal embrittlement (LME) of laser-deposition brazed CuSn12Ni2-c on 42CrMo4 using 2D-ratio thermography

Procedia CIRP, vol. 143, pp. 501–505

Abstract

Due to the beneficial tribological properties of bronze alloy CuSn12Ni2-c and similar materials, it is commonly used for brazing tempered steels such as 42CrMo4. Laser brazing is a modern process that offers several advantages for such material combinations, including effective thermal control and dense structures with high bonding strength. Challenges to process this materials system arise in the form of liquid metal embrittlement (LME), a well-known phenomenon where certain metals lose ductility to the point of fracture when in contact with certain liquid metals. It has been shown that this process is highly dependent on the transient temperature. Due to the complexity of measuring such high and dynamically changing temperatures, the exact analysis of temperature distributions, cooling rates, and heating in industrially relevant sample geometries is challenging. This work investigates the thermal influences of the brazing process on liquid metal embrittlement LME using a custom 2D-ratio thermography camera, combined with standard thermography. This investigation focuses on the relationship between transient temperature and the resulting LME phenomena such as length and number of cracks. Additionally, it serves as trials and qualification of the 2D-ratio thermography for the investigation of transient temperature during laser-powder deposition brazing.

Authors 8

1. Marcel Troise corresponding Aachen ISF – Welding and Joining Institute

   RWTH Aachen University

   Affiliation as printed

   RWTH-Aachen University, ISF - Welding and Joining Institute, Aachen, 52062, DE

2. Hannes Freiße
   Affiliation as printed

   Kugler Bimetal SA, Le Lignon, Geneva, 1219, Switzerland

3. Karthik Ravi Krishna Murthy Aachen ISF – Welding and Joining Institute

   RWTH Aachen University

   Affiliation as printed

   RWTH-Aachen University, ISF - Welding and Joining Institute, Aachen, 52062, DE

4. Konrad Mäde Aachen ISF – Welding and Joining Institute

   RWTH Aachen University

   Affiliation as printed

   RWTH-Aachen University, ISF - Welding and Joining Institute, Aachen, 52062, DE

5. Maximilian Gamerdinger Aachen ISF – Welding and Joining Institute

   RWTH Aachen University

   Affiliation as printed

   RWTH-Aachen University, ISF - Welding and Joining Institute, Aachen, 52062, DE

6. Vincent Heller Aachen ISF – Welding and Joining Institute

   RWTH Aachen University

   Affiliation as printed

   RWTH-Aachen University, ISF - Welding and Joining Institute, Aachen, 52062, DE

7. Simon Olschok Aachen ISF – Welding and Joining Institute

   RWTH Aachen University

   Affiliation as printed

   RWTH-Aachen University, ISF - Welding and Joining Institute, Aachen, 52062, DE

8. Uwe Reisgen Aachen ISF – Welding and Joining Institute

   RWTH Aachen University

   Affiliation as printed

   RWTH-Aachen University, ISF - Welding and Joining Institute, Aachen, 52062, DE