An adaptable flexural test fixture for miniaturised polymer specimens

Abstract

An adaptable flexural test fixture is proposed to characterise the mechanical properties of miniature beam specimens (�10 mg) at ambient conditions or in the presence of fluids at elevated temperatures. The fixture is validated using representative amorphous and semi-crystalline polymers. The response of miniature specimens is compared against that of medium-sized specimens (�1 g) on the same fixture and on conventional test equipment. Good agreement is found between the specimen sizes for all materials, but the comparisons highlight small differences attributed to factors such as specimen dimensional accuracy, crystallinity and span-to-thickness ratios. Flexural tests in water at 37 � C using both specimen sizes were performed to investigate the evolution of mechanical behaviour of hydrolytically degraded polylactides. Here, specimen size influences the diffusion timescale of acidic by-products which can reduce or enhance autocatalysis.

Exploiting Generative Design for 3D Printing of Bacterial Biofilm Resistant Composite Devices

“…This predicted distribution of material was tested by replicating this distribution in samples produced using our MM‐IJ3DP approach (5 × 2 × 0.7 mm 3 ). These printed samples were tested experimentally using a flexural test fixture [ 37 ] identical to that used in the model. When the prescribed deflection (0.250 mm) was reached at the center of the bespoke specimen beam, the observed load was 2.12 ± 0.22 N, in agreement with the designed load (2 N).…”

“…The test period was set to 10 min at a frequency of 1 Hz and 0.1% strain. The 3‐point bending tests were carried out with a custom‐built flexural test fixture [ 37 ] at ambient conditions. The thickness of the printed sample was measured by optical microscope picture of sample fractured within liquid nitrogen.…”

Jig and Fixture Redesign for Making Reamer on Head Cylinder

“…Fixture adalah sebuah alat bantu produksi yang digunakan untuk membantu memegang dan melokasikan benda kerja dengan cepat tanpa kesalahan Craig et al, (2020). Keberhasilan rancangan fixture dipengaruhi oleh beberapa aspek, diantaranya adalah aspek peletakan benda kerja, pencekaman, penanganan, kelonggaran, kekakuan atau stabilitas, material, dan toleransi (Choong et al, 2020) Desain jig dan fixture yang benar diatur oleh beberapa faktor di antaranya yaitu ditentukan melalui: a. Ukuran penjepit tertentu, yaitu tergantung pada gaya penjepit b. Mode dan kecepatan aktuasi, c. Jenis operasi pemesinan d. Fitur dan pertimbangan keselamatan, e. Di sisi lain, tidak pernah bisa sepenuhnya tergabung dalam algoritma tanpa penilaian yang tepat dari seorang desainer berpengalaman. Selanjutnya faktor umum yang harus dipertimbangkan saat mendesain jig dan fixture ditunjukkan pada Gambar 1.…”