Language
Differences Between Welding Identical Metals & Dissimilar Metals with Polymer Diffusion Welders
Jul 14,2026
Polymer diffusion welders are widely used for joining identical and dissimilar metals by virtue of atomic-level metallurgical bonding. Due to distinct material properties, significant differences exist in processes, technical difficulties and joint quality. Details are as follows:
I Differences in Welding Principles
1.Welding identical materials
Both workpieces share identical atomic structures and lattice types. Accurate control of temperature, pressure and time enables sufficient atomic diffusion and lattice reconstruction at contact surfaces to form uniform, dense metallurgical joints.
2.Welding dissimilar materials
The two base metals differ greatly in atomic structure, lattice type and physical & chemical properties. It is necessary to balance atomic diffusion and chemical reactions between dissimilar atoms simultaneously.
II Differences in Parameter Setting
1 Temperature Parameters
•Identical materials: Temperature control is relatively simple; only enough atomic diffusion needs to be guaranteed.
•Dissimilar materials: Take the metal with lower melting point as benchmark, adopt segmented temperature control and minimize temperature fluctuation to balance melting point gaps of two materials.
2 Pressure Parameters
•Identical materials: Pressure only needs to break oxide films and eliminate contact gaps; moderate uniformity requirement, no excessive pressurization.
•Dissimilar materials: Precisely adjust pressure to match different hardness and ductility; ensure tight contact while avoiding crushing low-plasticity metal layers.
3 Time Parameters
•Identical materials: Relatively short holding time, just enough to form proper diffusion layers.
•Dissimilar materials: Strict time control; overlong duration triggers excessive intermetallic reactions.
III Differences in Welding Difficulties
•Identical materials: Few technical obstacles; common defects include cold joints and incomplete penetration caused by incomplete surface pre-treatment or parameter drift. Standard cleaning and equipment calibration can solve them.
•Dissimilar materials: Brittle intermetallic compounds easily form, leading to joint cracking & peeling; mismatched thermal expansion coefficients generate large internal stress; oxides of two metals have different removal difficulty.
IV Differences in Joint Properties
•Identical metals: Uniform full metallurgical bonding, flat joint surface without welding marks.
•Dissimilar metals: Composite structure consisting of diffusion layer + reaction layer.
V Differences in Pre-Treatment & Auxiliary Processes
•Identical materials: Simple pre-treatment, only remove oil and oxide scales.
•Dissimilar materials: Targeted surface modification; intermediate barrier layers required for certain material combinations.
VI Application Scenarios & Operation Suggestions
1.Identical metal welding: Wide applicable range, easy equipment operation, suitable for mass high-efficiency production. Focus on stable parameters and complete pre-cleaning.
2.Dissimilar metal welding: Applied to high-end manufacturing. Coordinate all parameters, restrain chemical reactions and thermal stress deformation. Conduct small batch trial welding first to optimize processes before mass production.
Related News
Wuxi HAIFEI Intelligent Equipment Co., Ltd.
Wuxi HAIFEI Welding Equipment Co., Ltd.
Add: 28 Shuiyun Road, Yuecheng, Jiangyin, Jiangsu Province, China. (Postal Code: 214404)
Mobile: +86 18915302352
Email: wushijie@jshaifei.com