Also, solid-state stretching of beta-crystalline sheet results in the production of microvoids in the drawn product
. These microvoids increase the opacity of the drawn material, causing it to take on a white appearance due to light scattering from the voids.
Following determined values, tensile strength of wire and values, which were made for plasticity of material check, we can state that both materials are suitable to fulfill the requirements which are given for this specification of high-strength drawn product
Due to natural air circulation the bottom side of the drawn product will become cooler while the top portion anneals itself with the circulation of air around the tube.
At low draw ratios ([less than] 4.5) where post mandrel drawing is restricted by the water cooling arrangement, axial fracture strength is seen to be much higher than the yield strength due to the drawn product suffering little strain hardening.
After processing, drawn products were seen to be thicker on the bottom side than on the top.
They included the overall Apprentice of the Year Award, which went to Chris Blahuta, an electrical maintenance engineer, who is employed by Cold Drawn Products
There are horizontal connecting fibers, which we believe will improve the transverse tensile strength of the drawn products. This requires further investigation and testing.
Initial tensile testing of these hot drawn products shows retention of the good ductility at relatively high total draw ratios; see Fig.
This is further demonstrated by the Final drawn products. There is also visual evidence of transverse connecting fibrils in the drawn products, which suggests that the transverse tensile strength of the products should be better than in previous materials,
The changes in mechanical and structural properties might therefore be large along [X.sub.3], relatively small along [X.sub.2], and insignificant along [X.sub.1], unlike those for uniaxially drawn products for which [X.sub.2] and [X.sub.1] are indistinguishable.
To represent the isotropic material, a piece was machined from the original cylinder, with similar dimensions to the drawn products. A sample of the shavings from machining was sent to RAPRA for molecular weight measurements by gel permeation chromatography; two specimens gave [M.sub.w] = 6.62 x [10.sup.5], [M.sub.n] = 4.27 x [10.sup.4], and [M.sub.w] = 6.77 x [10.sup.5], [M.sub.n] = 5.00 x [10.sup.4].