1. Develop advanced wear and corrosion resistant materials and innovative surface engineering technologies to meet industry needs.

2. Contribute to the understanding of fundamental principles governing wear and corrosion phenomena.

1. Wear and corrosion resistant materials and coatings.
2. Pipeline steels, light weight alloys (Al and Mg).
3. Super-elastic and shape memory alloys, Ni-based electroless coatings.
4. Nano-crystalline materials and composites.

1. Tribology, friction, and wear.
2. Corrosion, erosion, micro-mechanical, and nano-mechanical testing.
3. Surface engineering and contact mechanics.
4. Nanotribology and structure-property-performance relationships.

Pipelines move nearly 75% of the oil transported annually worldwide and are, by far, the most important petroleum supply line for crude oil and gas. In addition to their efficiency, pipelines also have important environmental and safety benefits. Pipelines are subject to harsh environments and operating conditions that may cause failures with catastrophic consequences. One of the most common degradation processes is due to erosion-corrosion. The corrosion-related costs to the global transmission pipeline industry is approximately $50 billion annually, in addition to the irreversible damage to wildlife and the environment. The research work in this area focuses on pipeline integrity in onshore and offshore environments and is funded by several major national and internationals grants. Highlights of Dr. Farhat's contributions in this area are listed below.

1. Quantified the synergistic erosion-corrosion effects in API X-series oil and gas pipeline steels. For example, it was found that during erosion-corrosion of API X-70 in a CO2 environment, corrosion increases erosion by about 50%.

2. Discovered that, contrary to expectations, erosion under high particle feed rate, the velocity exponent η (E=kVη) decreases with increase in impact angle. It was concluded that, under such conditions, the velocity exponent η becomes mechanism dependent.

3. Proposed plausible mechanisms for solid particle erosion as functions of abrasive particle velocity and impact angle.

4. Demonstrated that the reason behind the good adhesion of the initial FeCO3 passive film in API X-42 steel in a CO2 environment, is due to the anchoring of the corrosion layer by the pearlite phase.

5. Found that the commonly observed passive film that develops in API X-42 steel in a sweet environment is made up of three corrosion layers. These layers are FeCO3 (primary), FeCO3 and Fe2O3 (secondary) and FeCO3, Fe2O3 and FeO (tertiary).

6. Demonstrated a significant sensitivity of carbon steel erosion to its microstructure. Analysis has shown the erosion rate is controlled by the type of micro-structural constituent, orientation of pearlite plates and the angle of the impinging particle, with respect to the steel surface.

7. Developed erosion mechanism maps for API-X series pipeline steels.

While super-elastic TiNi alloys have been around for a while, they have not been fully exploited for tribological applications. Dr. Farhat's work is directed towards understanding the wear and dent behaviour of these unique materials for use in tribological applications. One potential application of these alloys is in high precision bearings for the aerospace industry. Super-elastic bearings are expected to absorb the high impact loads experienced during take-off and landing by aircraft and space vehicles. Dr. Farhat's research in this area has attracted the attention of researchers at NASA Glen Research Centre, which led to a collaboration focused on extending the use of super-elastic materials to bearings in aerospace applications. Listed below are examples of Dr. Farhat's achievements in this area.

1. Discovered the existent relationship between loading rate and super-elasticity under localized indentation loading. At a high loading rate, super-elasticity drops by 10-15%, while accompanied by drop in dent resistance. This behaviour can have serious implications in applications where super-elastic TiNi is subjected to high impact loading.

2. Demonstrated that delimitation wear is a dominant wear mechanism in super-elastic TiNi due, in part, to the mismatch between elastic properties below the surface.

3. Modified the Oliver and Pharr method by incorporating phase transition effects, which take place during indentation into the model. The Oliver and Pharr method for calculating mechanical properties from load-indentation depth data, was developed for single-phase materials without phase transition. This method fails when extended to super-elastic TiNi, as the effective elastic modulus for such a material varies with indentation depth.

4. Demonstrated that new generations of aged and solution treated 60NiTi exhibit slightly enhanced super-elasticity compared to equiatomic TiNi (i.e., lower E/H), yet they show about 3 times the hardness and about 40% improvement in wear resistance.

5. Developed a model to predict the temperature rise in the transformation zone during indentation of super-elastic TiNi and found that, contrary to long held understanding, heat accumulation in the deformation zone during indentation is insignificant.

Throughout Dr. Farhat's career, he has worked on many wear and friction related projects. The general aims of these projects were to understand wear mechanisms in different materials under variety of conditions and develop surface treatments and coatings to mitigate wear. Examples of these contributions are below.

1. Successfully fabricated and assessed novel electroless Ni-P-based coatings; i.e., super-elastic Ni-P-NiTi and Ni-P-graphene composite coatings.

2. Developed an understanding of the role of surface chemistry and diffusion of atomic species across a tool-workpiece interface in high speed machining for cubic BN and WC-TiC-Co tools.

3. Developed a technique to experimentally determine elastic-plastic stress distribution under an indenter.

4. Developed a technique to monitor crystallographic anisotropy in Al and Ti alloys during wear, and discovered strong correlations between friction and wear and crystallographic texture evolution.

5. Characterized mechanical and thermal damage in hard chromium coatings.

6. Successfully developed novel wear resistant nano-crystalline (Al, Ti, Cu), quasicrystalline (Al-Cu-Fe) and nano-laminated composite (Al/Al2O3, Ti/TiN, Ti/Cu) films using a radio frequency triode magnetron sputtering system and reactive sputtering techniques.

7.Modified Archard’s law of wear in terms of the Hall-Petch equation for nano-laminated composites.

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