Week - 5 - Modelling Spotwelds

AIM:TO SIMULATE CRASH OF SPOT WELDED PLATES TO ARIGID WALL AND TO COMPARE BETWEEN BEAM AND SOLID TYPE OF SPOT WELD.

SPECIFICATION AND DATA:

THICKNESS OF PLATES-1.5 mm

VELOCITY OF PLATES -13.5 mm/ms

MATERIAL DATA:

STEEL DATA: DENSITY- 7.85E-3 , E-210000 , PR-0.3

MAT ELASTIC CARD (MAT001)IS USED FOR PLATES AND MAT SPOTEWLD (MAT100) IS USED FOR SPOT WELD.

SUMMARY/ANALYSIS SETUP:

• FIRST CREATE SECTION CARD FOR PLATE USING SHELL SECTION AND THICKNESS PF 1.2 mm IS ASSIGNED WITH EL FORM EQUAL TO 16. SIMILARLYBEAM SECTION IS CREATED WITH EL FORM 9.
• USING MAT 001 ELASTIC MATERIAL FOR SHELL PART AND MAT100 FOR SPOTWELD USING ABOVE DATA.
• TOTAL OF 6 SPOT WELD IS CREATED BETWEEN TWO PLATES USING BEAM ELEMENT.
• NOW ASSIGN SECTION AND MATERIAL CARDS TO PART.
• NOW ASSIGN INITIAL VELOCITY TO THE PART SET CREATED OF SHELL ELEMENTS IN NEGATIVE X DIRECTION.
• CREATE RIGID WALL AT A OFFSET DISTANCE OF 30mm FROM PLATE 1.
• NOW TO DEFINE CONTACT AUTO TIED EDGE TO SURFACE IS USED WHERE NODE SET CONNECTING BEAM ELEMENT IS SET AS SLAVE PART AND SHELL SET IS USED AS MASTER PART. ANOTHER CONTACT AUTO SINGLE SURFACE IS UED WHERE SHELL ELEMENT SET IS USED AS SLAVE SET.
• TOTAL ANALYSIS TIME IS SET TO 5 ms IN CONTROL TERMINATION.
• DATABASE D3PLOT WITH DT 0.1 IS SET AND IN ASCII GLSTAT,MATSUM, SWFCE IS SET.
• SHEARFORCE AND AXIAL FORCE IS CHECKED IN D3PLOT FOR RESULTS.
• SIMILARLY SOLID ELEMENTS ARE USED FOR MODELLING SPOTWELD AND SOLID SECTION IS USED WITH EFORM 1.

RESULTS:

AXIAL FORCE PLOT:

BEAM SPOTWELD

THE MAXIMUM AXIAL FORCE OF BEAM SPOTWELD IS 1.7KN.

SOLID SPOTWELD

THE MAXIMUM AXIAL FORCE OF SOLID SPOTWELD IS 320 N.

SHEAR FORCE PLOT:

BEAM SPOTWELD:

THE MAXIMUM SHEAR FORCE OF BEAM SPOTWELD IS 1KN.

SOLID SPOTWELD:

THE MAXIMUM SHEAR FORCE OF SOLID SPOTWELD IS 215N.