Effect of baking process on microstructures and mechanical properties of low silicon TRIP steel sheet with niobium

After 2% predeformation, the baking treatment with different schedule was carried out for low silicon TRIP steel sheet with niobium. The effects of baking temperature and time on microstructures and mechanical properties were investigated. The results showed that with increasing the baking temperature and time, the volume fraction of retained austenite decreases, and the volume fraction of tempered martensite increases; as baking temperature ranges from 80°C to 170°C, the bake-hardening (BH) value increases obviously, while from 170°C to 230°C, the variation of BH value is very slight; as baking time ranges from 2 min to 20 min, the BH value increases significantly, while the BH value decreases when baking time exceeds 20 min. So that when the baking temperature is 170°C and the baking time is 20 min, the low silicon TRIP steel sheet exhibits good bake-hardening behavior, and the highest BH value is above 70 MPa.

Effects of hydrocolloids on partial baking and frozen storage of wheat flour chapatti

The use of hydrocolloids in different foods systems has become more commonly applied to improve the texture and quality of baked products. Nevertheless, the effects of these compounds on partially baked frozen chapatti have not been studied. The objective of the present study was to improve the storage stability, quality and shelf life of partially baked chapatti by adding various hydrocolloids, hydroxyl propyl methylcellulose (HPMC), carboxy methylcellulose (CMC) and guar gum, followed by frozen storage for 28 days. Partially baked and fully baked chapattis after frozen storage were analyzed for chemical and sensory attributes at 7-day intervals. Rheological studies showed an increase in water absorption, dough development time and dough stability after the addition of hydrocolloids. In partially baked chapatti with hydrocolloids after frozen storage, an increase in moisture retention and water soluble starch was observed. Sensory characteristics were also improved by combining both techniques. Among the hydrocolloids, HPMC exhibited the best results, followed by CMC and guar gum. These hydrocolloids and partial baking with frozen storage helped to improve the quality, and extend the shelf life of partially baked chapatti.

Effects of aging bake hardenable steel in sheet metal forming

Bake hardening steels are being used as body panels in modern cars. These steels are stronger through an ageing process after baking in the paint ovens, which allows the thickness of the steel to be reduced without reducing the denting performance. The current study examined whether the steel ages at room temperature prior to forming which would deteriorate the formability. The work developed a new test and provided insight into acceptable levels of natural ageing which could be tolerated in the manufacturing process.

Effect of prestrain on microstructures and properties of Si-Al-Mn TRIP steel sheet with niobium

Paint baking treatment was carried out in a silicon oil bath at 170 °C for 20 min for Si-Al-Mn TRIP Steel sheet with different prestrains, and effect of prestrain on microstructures and properties was studied before and after baking. The results show that with the increasing of prestrain amount during prestraining and baking, the volume fraction of retained austenite decreases, and the volume fraction of martensite and bainite increases as well as yield strength increases; as prestrain ranges from 0 to 4%, the baking-hardening (BH) value increases; while the prestrain ranges from 4% to 16%, the BH value decreases; when the prestrain amount is 4%, the highest BH value is about 70 MPa for Si-Al-Mn TRIP steel sheet with niobium, which displays excellent baking-hardening behavior.

A protocol for improving fabrication yield of thin SU-8 microcantilevers for use in an aptasensor

SU-8 negative photoresist has been extensively employed in the fabrication of microfluidics and microelectromechanical systems. This is due to its advantages including ease of fabrication using limited equipment, biocompatibility, excellent chemical resistance, and compatibility with silicon processing. In addition, its low Young’s modulus compared to silicon has made it an excellent choice for microcantilever structure development especially for sensing applications. This paper presents a fabrication protocol for the development of thin SU-8 microcantilevers. Factors such as baking temperatures and release methods that influence the fabrication yield of SU-8 microcantilevers are considered. The influence of the baking temperature on the deformation of the SU-8 structure is investigated using the finite element method and verified experimentally. Three release methods are studied including a dry release method using fluorocarbon film, and two wet release methods using OmniCoat sacrificial layer and polymethyl methacrylate (PMMA) sacrificial layer. The wet release method using PMMA sacrificial layer produced the highest yield. An aptasensor is formed using the SU-8 microcantilever, and its deflection measured for thrombin detection.

Productivity growth as a barrier to a sustainability transition

The need for strong productivity growth is a prominent feature of economic policy debates in Australia. Using the productivity trap concept, this viewpoint explores how in some circumstances the pursuit of productivity growth is a barrier to effective sustainability transitions. This is illustrated by a case study of the Australian baking industry, where the increased market share of small-scale artisan bakers vis-à-vis industrial bakers has recently led to an overall decline in productivity across the baking sector. Although artisan bakers produce more nutritious products and have the potential to significantly increase the energy efficiency of their operations, their labour productivity is half that of their industrial counterparts. Whilst this is good for employment, public health and the environment, artisan bakers have been denigrated as a ‘drain on productivity’. This case study illustrates the potential role of low-productivity goods and services in a sustainability transition in Australia and other developed countries.

Xylanolytic modification in wheat flour and its effect on dough rheological characteristics and bread quality attributes

Effects of various xylanase treatments applied at different stages of bread making process on dough rheological characteristics and bread quality attributes were investigated. Different doses (200, 400, 600, 800, and 1000 IU) of purified enzyme were applied at two stages (tempering and mixing). In milling and dough making processes, both types of flour (subjected to enzyme treatment during tempering and flour mixing) exhibited decreasing trend in water absorption, dough development time, dough stability, softening of dough, dough mixing time, viscosity peak, set back, and increasing tendency in peak height and pasting temperature. Treatments during tempering resulted in more significant effects as compared to applications during flour mixing. The dough rising during proofing resulted in enhancement from 137±3.21% (control) to maximum value (192.33±2.90%), when 600 IU of xylanases were applied to 1 kg of wheat grains during tempering. The bread sensory attributes also exhibited significant improvement in response to various doses of purified enzymes.