MAY 2003 -S 116 ABSTRACT. Mechanical characteristics of resistance spot welding machines, such as stiffness, friction, and moving mass, have complex influences on the resistance welding process and weld quality. In this paper, these influences are systematically investigated through experiments. The mechanisms of the influences are explored by analyzing process signatures, such as welding force...

tan films with different n2 partial pressure were deposited on 304 stainless steel using the magnetron sputtering method. the effect of gas pressure on the mechanical property, morphology and phase structure of the films is investigated by x-ray diffraction (xrd), atomic force microscopy (afm), microhardness testing, friction coefficient measurements, and wear mechanism study. the xrd results c...

friction stir processing was applied for fabricating an aluminum alloy based hybrid nano composite reinforced with nano sized al2o3 and micro sized graphite particles. a mixture of al2o3 and graphite particles was packed into a groove with 1 mm width and 4.5 mm depth, which had been cut in 5083 aluminum plate of 10 mm thick. packed groove was subjected to friction stir processing in order to im...

Titanium and its alloys are widely used in aircraft, rocket production, shipbuilding, machine industry, chemical and food industry, medicine due to their high specific strength, good corrosion resistance and biological passivity. However, titanium has properties which limit its application as construction material. Particularly, tendency to surface adhesion and galling at friction results in it...

We consider slip with friction and penetration with resistance boundary conditions in the steady state Navier– Stokes equations. This paper describes some aspects of the implementation of these boundary conditions for /nite element discretizations. Numerical tests on twoand three-dimensional channel 2ows across a step using the slip with friction boundary condition study the in2uence of the fri...

Tribology is the science and technology of interacting solid surfaces in relative motion, and its topics include the study of lubricants, lubrication, friction, wear, and bearings. It is estimated that friction and wear cost the US economy 6% of the gross national product [1]. For example, 5% of the total energy generated in an automobile engine is lost to frictional resistance. Also notable ar...

Friction plays a key role in how ruptures unzip faults in the Earth's crust and release waves that cause destructive shaking. Yet dynamic friction evolution is one of the biggest uncertainties in earthquake science. Here we report on novel measurements of evolving local friction during spontaneously developing mini-earthquakes in the laboratory, enabled by our ultrahigh speed full-field imaging...

a simplified approach for nonlinear analysis of the load-displacement response of a single pile and a pile group is presented using the load-transfer approach. a hyperbolic model is used to capture the relationship between unit skin friction and pile-soil relative displacement developed at the pile-soil interface and the load-displacement relationship developed at the pile end. as to the nonlin...

Melt produced by friction during earthquakes may act either as a coseismic fault lubricant or as a viscous brake. Here we estimate the dynamic shear resistance (tau(f)) in the presence of friction-induced melts from both exhumed faults and high-velocity (1.28 meters per second) frictional experiments. Exhumed faults within granitoids (tonalites) indicate low tau(f) at 10 kilometers in depth. Fr...