Experimental Study of a Full Forward Extrusion Process from Metal Strip

A high rate of production of complex microparts is increasingly required by fields like electronics and micromechanics. Handling is one of the main problems, limiting those forming processes of small metal components consisting of multiple forming stages. A forming chain in which a metal strip acts both as raw material and support of the workpiece through the different stages of the process, is seen as a solution that radically simplifies the positioning of microparts. Each workpiece stays connected to the strip through all the forming steps, being separated just at the end of the process chain. In this work, a tooling system for the bulk forming from copper strips has been set up and employed in a full forward extrusion process of a micro-billet. The same die, with a diameter of 1 mm, has been used with three different strip thicknesses (1, 2 and 3 mm) and three different material conditions. The use of thinner and hard-as-rolled strips has resulted in achieving a higher ratio of the billet length to strip thickness.

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Simulation of a Full Forward Extrusion Process from Metal Strip

10.1063/1.3589563 ◽

2011 ◽

Cited By ~ 3

Author(s):

Marion Merklein ◽

Tommaso Stellin ◽

Ulf Engel

Keyword(s):

Extrusion Process ◽

Metal Strip ◽

Forward Extrusion

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Experimental and Numerical Investigation on a Full Forward Extrusion Process from Metal Strip

Proceedings of the 9th International Conference on Multi-Material Micro Manufacture ◽

10.3850/978-981-07-3353-7_274 ◽

2012 ◽

Cited By ~ 1

Author(s):

Stellin T ◽

Engel U ◽

Merklein M

Keyword(s):

Numerical Investigation ◽

Extrusion Process ◽

Metal Strip ◽

Forward Extrusion

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Process chain for the manufacture of hybrid bearing bushings

Production Engineering ◽

10.1007/s11740-021-01028-4 ◽

2021 ◽

Vol 15 (2) ◽

pp. 137-150

Author(s):

Susanne Elisabeth Thürer ◽

Anna Chugreeva ◽

Norman Heimes ◽

Johanna Uhe ◽

Bernd-Arno Behrens ◽

...

Keyword(s):

Extrusion Process ◽

Steel Tube ◽

Case Hardening ◽

Process Chain ◽

Forming Process ◽

Die Forging ◽

Material Contact ◽

Hybrid Bearing ◽

Case Hardening Steel ◽

Tailored Forming

AbstractThe current study presents a novel Tailored Forming process chain developed for the production of hybrid bearing bushings. In a first step, semi-finished products in the form of locally reinforced hollow profiles were produced using a new co-extrusion process. For this purpose, a modular tool concept was developed in which a steel tube made of a case-hardening steel, either C15 (AISI 1015) or 20MnCr5 (AISI 5120), is fed laterally into the tool. Inside the welding chamber, the steel tube is joined with the extruded aluminum alloy EN AW-6082. In the second step, sections from the compound profiles were formed into hybrid bearing bushings by die forging. In order to set the required forming temperatures for each material—aluminum and steel—simultaneously, a tailored heating strategy was developed, which enabled successful die forging of the hybrid workpiece to the desired bearing bushing geometry. Using either of the case-hardening steels in combination with aluminum, this novel process chain made it possible to produce intact hybrid bearing bushings, which showed both macroscopically and microscopically intimate material contact inside the compound zone.

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MECHANICAL PROPERTIES OF ROTATIONALLY MOLDED PET MICROFIBRIL REINFORCED COMPOSITES

International Journal of Modern Physics B ◽

10.1142/s021797920604177x ◽

2006 ◽

Vol 20 (25n27) ◽

pp. 4613-4618 ◽

Cited By ~ 3

Author(s):

R. J. T. LIN ◽

D. BHATTACHARYYA ◽

S. FAKIROV

Keyword(s):

Mechanical Properties ◽

Manufacturing Industry ◽

Polymer Processing ◽

Raw Material ◽

Medium Density ◽

Reinforced Composites ◽

Rotational Molding ◽

Commercial Scale ◽

Strength And Stiffness ◽

Set Up

Being a fast growing plastic manufacturing industry, rotational molding has been using the linear polyethylenes extensively as the raw material. As these materials have shown insufficient mechanical properties for certain applications where strength and stiffness of the products are the main concerns, worldwide rotational molders have expressed a need for stronger and stiffer materials to be available for rotomolding. A possible attractive solution may be the recently developed microfibril reinforced composites (MFCs). Blends of linear medium density polyethylene/polyethylene terephthalate (LMDPE/PET) with an MFC structure are manufactured on a commercial-scale set-up and thereafter used in rotational molding. The samples are characterized morphologically and tested mechanically. The results obtained show that the MFC-concept has good application opportunities in the polymer processing including rotational molding.

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High-Moisture Meat Analogues Produced from Yellow Pea and Faba Bean Protein Isolates/Concentrate: Effect of Raw Material Composition and Extrusion Parameters on Texture Properties

Foods ◽

10.3390/foods10040843 ◽

2021 ◽

Vol 10 (4) ◽

pp. 843

Author(s):

Ferawati Ferawati ◽

Izalin Zahari ◽

Malin Barman ◽

Mohammed Hefni ◽

Cecilia Ahlström ◽

...

Keyword(s):

Faba Bean ◽

Genetically Modified Organisms ◽

Extrusion Process ◽

Raw Material ◽

High Moisture ◽

Protein Isolates ◽

Factors Affecting ◽

Texture Properties ◽

Meat Analogue ◽

Bean Protein

Yellow pea and faba bean are potential candidates to replace soybean-based ingredients due to their suitability for cultivation in the northern hemisphere, non-genetically modified organisms cultivation practice and low risk of allergenicity. This study examined the functionality of local yellow pea and faba bean protein isolates/concentrate as meat analogue products. The most critical factors affecting the texture properties of meat analogue were also determined. Extrusion was used to produce high-moisture meat analogues (HMMAs) from yellow pea and faba bean protein isolates/concentrates and HMMAs with fibrous layered structures was successfully produced from both imported commercial and local sources. The texture properties of the HMMA produced were mainly affected by the ash, fiber and protein content and water-holding capacity of the source protein. Three extrusion process parameters (target moisture content, extrusion temperature, screw speed), also significantly affected HMMA texture. In conclusion, functional HMMA can be produced using protein isolates derived from locally grown pulses.

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Setting Up a Lab-Scale Pilot Plant to Study the New Growing System (NGS®) for Leafy Vegetable and Culinary Herb Growth

Horticulturae ◽

10.3390/horticulturae7050090 ◽

2021 ◽

Vol 7 (5) ◽

pp. 90

Author(s):

Silvana Nicola ◽

Giuseppe Pignata ◽

Manuela Casale ◽

Saeid Hazrati ◽

Andrea Ertani

Keyword(s):

Pilot Plant ◽

Raw Material ◽

Leafy Vegetables ◽

Plant Densities ◽

Culinary Herbs ◽

Soilless Cultivation ◽

Set Up ◽

High Yields ◽

Leaf Vegetable ◽

Nutrient Solutions

New cultural techniques have been developed to improve the yield and raw material quality at harvest, and enhance the postharvest shelf life, by standardizing the growing system. Among the different Soilless Cultivation Systems, the New Growing System (NGS®) is a closed-recirculating system that was designed for open fields and protected cultivations. The aim of this work was to investigate the structural setting of the system and its functioning to harness the full potentiality of NGS®. A lab-scale pilot plant (LSPP) was designed with NGS® technology and the technical aspects have been set up to have a standardized and reproducible growing system. The trials were conducted on growing mature-leaf vegetable species; that is, on both head and multi-leaf vegetables, and on culinary herbs at high plant densities. Positive yield results were found for culinary herbs and leafy vegetables. Mints showed high yields for the two re-growths carried out after the first harvest. The LSPP can also be used in a series of reliable experiments and enable researches to test several species, substrates, hydroponic nutrient solutions, and fertigation scheduling.

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Paternity, relationship, sexual activity and fertility in testicular cancer (TC) survivors (TCS): Results from a single institution observational prospective study.

Journal of Clinical Oncology ◽

10.1200/jco.2021.39.6_suppl.380 ◽

2021 ◽

Vol 39 (6_suppl) ◽

pp. 380-380

Author(s):

Davide Bimbatti ◽

Francesco Pierantoni ◽

Marco Maruzzo ◽

Filippo Maria Deppieri ◽

Aichi Msaki ◽

...

Keyword(s):

Sexual Dysfunction ◽

Premature Ejaculation ◽

Relative Survival ◽

High Dose Chemotherapy ◽

High Rate ◽

Interdisciplinary Management ◽

High Dose ◽

Family Status ◽

Set Up ◽

Status Data

380 Background: TC represents 1% of male neoplasms but it is the most common in young adults. Interdisciplinary management with chemotherapy, radiotherapy and surgery has led to a 10-year relative survival rate of up to 95%. These treatments (Tx) have short- and long-term side effects. While sexual dysfunction can reduce fertility, psychosocial distress can create relationship problems and finally affect the ability to procreate. Methods: From February 2020, we submitted a series of questionnaires to all the patients (pts) currently followed-up at the Istituto Oncologico Veneto free from TC recurrence for at least 2 years from the last Tx. International Index of Erectile Function (IIEF-15) and Premature Ejaculation Diagnostic Tool (PEDT) were used. We also set up a questionnaire to investigate paternity and family status. Data about disease and treatments were collected from medical records. Results: 84 TCS completed the questionnaires, clinical data are reported in the table below. 29,8% of pts fathered children before diagnosis with a strong correlation with older age at diagnosis (45,4 vs 30,8 years, p<0,001). After Tx, 14 pts had children: 9 of which naturally, 2 out 6 were successful via assisted reproductive technology (ART) (including one patient that received high-dose chemotherapy and stem cell transplantation), 3 via adoption. 89,3% of pts had stable relationships. Of pts who did not have children: 13,1% claimed to be due to lack of a partner, 39,3% claimed to be unready, while 14,3% had tried unsuccessfully to conceive. While 28,6% pts claim to currently have fertility issues, only 8,3% of pts reported to have these issues before diagnosis. 70,2% of pts performed a spermiogram after Tx, 10 pts had spermatogenic impairment. Higher rate of sexual dysfunction after Tx was detected by questionnaires while only 4 pts claimed to have had a pre-existing issue prior to TC diagnosis. PEDT shows that 38,1% had premature ejaculation and that in 22,6% this issue is highly probable. IIEF confirms a high rate of erectile dysfunction (14,3% severe and 10,7% mild or moderate). No correlations were identified between sexual dysfuntion and previous Tx. Conclusions: Most TCS had not planned fatherhood while 16,7% had children after Tx and 14.3% tried unsuccessfully to conceive. ART and adoption is possible but challenging and little used. PEDT and IIEF found high rates of sexual dysfunction but no association with previous Tx were found. [Table: see text]

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Ciliary Activity and Oxygen uptake in Branchiostoma Lanceolatum(Pallas)

Journal of Experimental Biology ◽

10.1242/jeb.43.1.1 ◽

1965 ◽

Vol 43 (1) ◽

pp. 1-12

Author(s):

W. A. M. COURTNEY ◽

R. C. NEWELL

Keyword(s):

Oxygen Uptake ◽

High Rate ◽

Ciliary Activity ◽

Oxygen Utilization ◽

Nervous Control ◽

Pharyngeal Wall ◽

Temperature Range ◽

Zero Rate ◽

Branchiostoma Lanceolatum ◽

Set Up

1. The rate of oxygen uptake by single specimens of Branchiostoma lanceolatum has been shown to vary considerably. Some animals in sealed vessels at 50° C. were able to utilize the oxygen linearly down to less than 20% of air saturation. Others ceased to absorb oxygen at high saturations while yet others displayed two different rates in a sequence starting initially with a high rate. 2. There are three possible rates of oxygen utilization, as well as a zero rate, for an animal at any temperature between 10 and 19° C. Animals in gravel exhibit only two rates at lower temperatures. 3. The slowest rate varies exponentially with temperature but the two faster rates show a rapid increase between 10 and 15° C. with little change outside this temperature range. 4. The effect of size and temperature on the increased oxygen uptake during the faster rates of respiration are discussed. It is suggested that ciliary activity of the pharynx could be associated with the extra oxygen utilization. 5. It has been found that there are three inhalant stream velocities, a fast, a slow and a zero rate with no intermediate rates. 6. Study of the isolated portions of the pharyngeal wall confirm that the fast inhalant current is set by the activity of all the cilia to give a feeding stream. The slow stream is set up by the lateral cilia, which continue to beat when the frontal cilia and most of the lateral cilia have been inhibited by lowered oxygen concentrations. 7. The lateral cilia have been shown to be under nervous control and to be inhibited by pressure on the pharyngeal bars. This mechanism depends on the presence of a connexion between the pharyngeal bars and the endostyle.

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