This paper presents a micromechanics-based elastoplastic damage model for quasi-brittle rocks in compression stress state. The plastic strain is considered to be related to frictional sliding along microcracks and inherently coupled with damage evolution. By following a homogenization procedure, we first determine the free energy for the matrix-cracks system. The thermodynamic force associated ...

A new near-net forging procedure of titanium and alloys was proposed by using a carbon-supersaturated punch die. Due to the in situ formation carbon-based tribofilm on contact interface between dies work materials, low frictional state sustained through process even high reduction thickness. The hardening suppressed during forging; an additional annealing unnecessary whole forging. Pure ?-phase...

The self-healing of strain-hardening cementitious composites (SHCCs) causes the recovery debonded fiber-to-matrix interface by products autogenous healing (mainly calcium carbonates). chemical bond G d has been detected in reactive magnesia cement (RMC)-based SHCC (SHMC), and frictional τ 0 both SHMCs normal SHCCs. While these phenomena can significantly alter fiber-bridging σ-w relationship SH...

This paper presents a framework for modeling failure in quasi-brittle geomaterials under different loading conditions. A micromechanics-based model is proposed which the field variables are linked to physical mechanisms at microcrack level: damage related growth of microcracks, while plasticity frictional sliding closed microcracks. Consequently, hardening/softening functions and parameters ent...

in this paper, a novel technique on friction aided deep drawing using tapered blank holder divided into eight segments is proposed to overcome defect of friction aided deep drawing using four segments tapered blank holder technique. a taper blank holder is designed to be of two parts: stationary part with 5 degree taper angle and moving parts divided into eight tapered segments. the main functi...

[1] Slide-hold-slide friction experiments are reported on fault gouges of salt and salt-muscovite mixtures to investigate the effects of fluids and phyllosilicates on strength gain. Healing rates of salt gouges in the presence of saturated brine are an order of magnitude higher than dry salt and water-saturated quartz at 65 C. Fault gouges consisting of salt-muscovite (80:20) mixtures show heal...