Performance Tests of HX340 Microalloyed Steel Sheets Joined Using Clinch-Rivet Technology

Area of Science:

• Materials Science and Engineering
• Manufacturing Processes
• Mechanical Engineering

Background:

• Investigates the formation of pressed joints between two 1.5 mm thick HX340 steel sheets.
• Utilizes a deformable steel rivet (400HV1 hardness) as the joining element.
• Examines the influence of rivet pressing depth and die depth on joint characteristics.

Purpose of the Study:

• To determine the possibility of forming pressed joints between HX340 steel sheets.
• To analyze the effect of varying rivet press-in depths and die depths on interlock geometry and joint strength.
• To quantify the relationship between process parameters and the resulting interlock size and load capacity.

Main Methods:

• Performed forming tests using an 'SKB' die with three different die depths (1.45, 1.60, 1.75 mm).
• Varied rivet pressing distances below the upper sheet surface (0, 0.15, 0.30, 0.45, 0.60 mm).
• Measured geometric dimensions of the interlock and conducted shear tests to analyze joint strength.

Main Results:

• A 20% increase in die depth (1.45 to 1.75 mm) at 0% rivet press-in depth reduced forming force by 12% and maximum load capacity by 3.5%.
• Increased rivet press-in depth (o) directly correlated with a larger interlock size (t).
• Increasing rivet press-in depth from 0 to 0.6 mm resulted in interlock size increases of 136% (h=1.45mm), 128% (h=1.60mm), and 85% (h=1.75mm).

Conclusions:

• Pressed joints can be successfully formed between HX340 steel sheets using deformable steel rivets.
• Rivet press-in depth is a critical parameter significantly influencing interlock size and, consequently, joint strength.
• Die depth affects forming force and load capacity, indicating a complex interplay between process parameters in clinch-riveting.