A novel processing route for the manufacture of EN AW 6082 forged components

© 2015 W. S. Maney & Son Ltd.An attractive combination of strength and formability, corrosion resistance and recyclability has made the age-hardening EN AW 6082 one of the most popular aluminium forging alloys. 6082 alloy forgings are thus used extensively in automotive suspension components. The conventional manufacturing cycle starts with the casting of 6082 billets that are subsequently extruded into smaller diameter forging stock. The relatively higher temperatures generated by frictional heating and high strains introduced at the surface during extrusion encourage recrystallisation and produces a heterogeneous structure with fully recrystallised small grains at the surface, fibrous grains at the centre. Hence, the surface of the forged 6082 components inevitably undergoes grain growth once exposed to high temperatures during the solution heat treatment. An attempt was made in the present work to identify an alternative process to achieve a homogeneous section structure with no evidence of coarse grains across the section, which in turn will ensure a better fatigue performance and a longer service life

Effects of continuous theta burst transcranial magnetic stimulation on cortical excitability in patients with idiopathic generalized epilepsy.

Introduction Transcranial magnetic stimulation (TMS) is a noninvasive technique for investigating cortical physiologic functions in the brain. In this study, the effects of continuous theta burst stimulation (cTBS) on motor evoked potential (MEP) parameters in patients with idiopathic generalized epilepsy (IGE) were investigated. Materials and methods Fifteen patients with IGE were included. Motor threshold (MT) and cortical silent period (CSP) were determined before cTBS application. Next, cTBS was applied to the dominant (left) hemisphere M1 hand area as the first application. After 1 day, cTBS was applied first to the left M1 hand area and then to the right lateral cerebellar area as the second application. Parameters were again determined after the applications. Results There was no difference in resting MT values before and after cTBS application (p > 0.05). Although CSP increased after stimulation (p 0.05). Conclusion For patients with epilepsy, cTBS is a safe technique when applied at a low intensity. The inhibitory effect of cTBS, a noninvasive technique, on cortical excitability in patients with IGE was determined using MEP parameters. The effect lasted at least 1 h. To our knowledge, this is the first study to assess the effect of cTBS on cortical excitability in patients with IGE. Our findings indicate that cTBS decreases cortical excitability in patients with IGE

Serial proton spectroscopy in a case of adult-onset subacute sclerosing panencephalitis.

A case of subacute sclerosing panencephalitis in a 27-year-old man was serially evaluated with proton magnetic resonance spectroscopy. Metabolic abnormalities included decreased N-acetylaspartate and elevated choline and myo-inositol in a lesion visible on magnetic resonance imaging and in normal-appearing white matter. Lactate appeared increased within the lesion. Metabolic impairment was persistent after intrathecal interferon-alpha treatment. Spectroscopy pointing to ongoing inflammation, gliosis, and possible membrane turnover was more sensitive than imaging in detecting widespread pathology within the white matter

Effect of Copper on Corrosion of Forged AlSi1MgMn Automotive Suspension Components

Recently, modifications in the alloy composition and the manufacturing process cycle were proposed to achieve a more uniform structure with no evidence of coarse grains across the section of the AlSi1MgMn alloys. Cu was added to the AlSi1MgMn alloy to improve its age hardening capacity without a separate solution heat treatment. However, Cu addition degrades the corrosion resistance of this alloy due to the formation of Al-Cu precipitates along the grain boundaries that are cathodic with respect to the aluminum matrix and thus encourage intergranular corrosion. The present work was undertaken to identify the impact of Cu addition on the corrosion properties of AlSi1MgMn alloys with different Cu contents. A series of AlSi1MgMn alloys with 0.06-0.89 wt.% Cu were tested in order to identify an optimum level of Cu addition