Characterization of the texture evolution in AISI 430 and AISI 433 ferritic stainless steels during simulated hot rolling

Multi-pass compression tests were carried out on the Gleeble-1500D® and Gleeble-3800TM® thermo-mechanical simulators to investigate the effect of temperature, strain rate and inter-pass time on the development of the texture in ferritic stainless steels (FSS) AISI 430 and 433, the latter an Al-containing variant. Orientation Distribution Functions (ODFs) through the electron backscattered diffraction (EBSD) technique was employed to characterise and study the texture present in the steels after hot working. The mean flow stress analysis showed that, the dynamic recrystallization to dynamic recovery transition temperature decreases with an increase in strain rate in both grades of stainless steels possibly allowing texture optimisation at lower hot rolling temperatures. Higher finishing rolling temperatures, lower strain rates and longer inter-pass times led to improvement in the formation of the desired γ-fibre texture which contributes to ductility or drawability in these steels. Dynamic recrystallization which promotes the formation of the desired γ-fibre texture was found to occur in both AISI 430 and 433 at temperatures above 1000 °C and strain rates less than 5 s-1. Generally AISI 433 develops a stronger gamma texture than the AISI 430 when hot rolled under similar conditions.

In Situ Tensile Texture Analysis of a New Mg-RE Alloy

A new Mg-RE (rare earth) alloy was previously developed by micro-alloying method (RE< 0.4 wt.%), which achieves a high ductility and good corrosion resistance. In-situ tensile test via neutron and synchrotron diffraction were performed to investigate first the deformation behaviour; and second the texture evolution which can be related to the deformation mechanism, and finally to understand why the as-cast Mg-RE alloys show such a high tensile ductility.Preliminary results showed that a dominated basal fibre texture was gradually developed with the increase of tensile strain. However, before the sample was broken a (10.0) fibre texture showed a similar intensity to that in (00.2), which means more activations of the non-basal slip planes during tensile deformation. This could also contribute to a relatively high elongation of this new Mg-RE alloy at room temperature. Further discussion will be showed together with the microstructures.

Filling in Losses in Parchment Bound Volumes – Part I: Assessment of Parchment and Paper Fibres in Reconstituted Parchment

Reconstituted parchment is, besides Japanese paper and parchment, a feasible and widely used material for filling in losses in parchment. This study investigates changes in haptic and visual qualities of the material caused by modifications with different ingredients like paper and parchment fibres. Additionally, selected procedures processing parchment to parchment powder were examined. As a brief introduction, the paper gives an overview over the existing types of reconstituted parchment that are used traditionally in parchment conservation. In addition it attempts to clarify the terminology for this material. Parchment powder was produced with simple and readily available equipment, by different methods: sanding, grating, grinding, shredding, milling and ice-crushing. The different types of home-made powder were compared to a pre-fabricated parchment powder obtained from a parchment maker. The test series showed that the type of preparation of parchment powder influences the fibre texture which in turn affects the material’s properties visually and haptically. While all methods are clearly more time-consuming than buying ready-to-use material, some preparations, e.g. grating, shredding and ice-crushing, showed superior properties.

The Effect of Homogenization Conditions on Extrusion Texture and Microstructure Evolution in AA3003

Two different conditions were used to study the effect of homogenization on extrusion texture and microstructure evolution in AA3003. The first condition considered homogenization for 8 h at 500°C to obtain a high density of dispersoids and the other condition was homogenized for 24 h at 600°C to produce a sample with a very low density of dispersoids. After uniaxial extrusion at 400°C with a speed of 32 mm/s and an extrusion ratio of 70:1, the material with a high density of dispersoids formed <001> and <111> double fibre texture in the centre of extrusion rod and a smeared texture from <011> to <111> near the surface. For the material without dispersoids, only <001> texture fibre is observed in the centre of extrusion rod and a strong <011> fibre is observed near the surface.