scholarly journals The Present State of Surface Conditioning in Cutting and Grinding

2021 ◽  
Vol 5 (3) ◽  
pp. 92
Author(s):  
Benedict Stampfer ◽  
Germán González ◽  
Michael Gerstenmeyer ◽  
Volker Schulze

All manufacturing processes have an impact on the surface layer state of a component, which in turn significantly determines the properties of parts in service. Although these effects should certainly be exploited, knowledge on the conditioning of the surfaces during the final cutting and abrasive process of metal components is still only extremely limited today. The key challenges in regard comprise the process-oriented acquisition of suitable measurement signals and their use in robust process control with regard to the surface layer conditions. By mastering these challenges, the present demands for sustainability in production on the one hand and the material requirements in terms of lightweight construction strength on the other hand can be successfully met. In this review article completely new surface conditioning approaches are presented, which originate from the Priority Program 2086 of the Deutsche Forschungsgemeinschaft (DFG).

1970 ◽  
Vol 79 ◽  
Author(s):  
Claus Peter Zoller

As can be seen, the title and subtitle of the book under review are part of the title of the following review article. A normal book review starts with some sentences describing what the book is about, followed by a discussion what the reviewer particularly likes about the book, and then followed by bringing up anything the reviewer dislikes about it. This is then rounded up with some general observations and appraisals. This strategy is also a broad guideline for the first third of the following text. However, the text also oversteps considerably the boundaries of a standard book review for the following reasons: Augusto Cacopardo defines his ‘Peristan’2 as a culturally quite coherent area extending through the high mountains from northwestern Afghanistan throughout the northern regions of Pakistan to the southwestern border of Tibet.3 The traditional cultures of this ‘Peristan’ have Indo-Iranian and even Indo-European roots, yet they are, in his opinion, remarkably little affected by the high civilizations of India and pre-Islamic Iran.4 However, it is important to understand that ‘Peristan’ has, on the one hand, indeed preserved archaisms not found elsewhere in South Asia, but due to strong influence of Islam it has also simultaneously lost, or preserved only sporadically, cultural traditions still authentically preserved e.g. in the Indian Himalayas. Cacopardo’s analysis of the Kalasha winter feasts has a strong historical-cultural dimension and he repeatedly refers to cultural parallels in the Himalayas (see section 7. ‘The Hindus of the Himalayas’, pp. 235ff.). His observations on these parallels – which are absolutely justified – nevertheless also caused me to trespass the boundaries of a book review and extend it considerably into a review article. Since the true frontiers of ‘Greater Peristan’ enclose in my view a significantly larger geographical area than envisaged by the Cacopardo Brothers,5 the following article presents also very many data not found or discussed in the publication under review. In order to keep a clear overview of this long review article, it has been divided into four main sections. However, ‘Section I’ only follows after the ‘Preliminary remarks’ and the ‘Opening’:


1964 ◽  
Vol 54 (1) ◽  
pp. 417-423
Author(s):  
H. Deresiewicz

abstract The classical solution of Stoneley and Tillotson is generalized by considering the outer one of the pair of layers to be porous. Although the dispersion relation turns out, for practical purposes, to be identical with the one governing the classical case, the motion in the present instance is shown to be dissipative and the expression is exhibited for the specific energy loss.


2019 ◽  
Vol 44 (6) ◽  
pp. E289-E298 ◽  
Author(s):  
CRG van den Breemer ◽  
M Özcan ◽  
MS Cune ◽  
AP Almeida Ayres ◽  
B Van Meerbeek ◽  
...  

SUMMARY This study evaluated the microtensile bond strength (μTBS) of resin-based composite (RBC) to dentin after different immediate dentin sealing (IDS) strategies and surface-conditioning (SC) methods and on two water storage times. Human molars (n=48) were randomly divided into eight experimental groups involving four different IDS strategies—IDS-1L with one layer of adhesive, IDS-2L with two layers of adhesive, IDS-F with one layer of adhesive and one layer of flowable RBC, and DDS (delayed dentin sealing) with no layer of adhesive (control)—and two different SC methods—SC-P with pumice rubbing and SC-PC with pumice rubbing followed by tribochemical silica coating. The μTBS test was performed after one week and after six months of water storage, being recorded as the “immediate” and “aged” μTBS, respectively. Composite-adhesive-dentin microspecimens (0.9×0.9×8–9 mm) were stressed in tension until failure to determine the μTBS. Failure mode and location of failure were categorized. Two-way analysis of variance was applied to analyze the data for statistically significant differences between the experimental groups (p<0.05). Two-way analysis of variance revealed no significant differences between the one-week μTBS specimens for IDS strategy (p=0.087) and SC methods (p=0.806). However, the interaction of IDS strategy and SC methods appeared statistically significant (p=0.016). The six-month specimen evaluation showed no significant difference in μTBS for SC (p=0.297) and SC/IDS interaction (p=0.055), but the μTBS of the IDS strategies differed significantly among them (p=0.003). For tribochemical silica-coated IDS, no significant effect of aging on μTBS was recorded (p=0.465), but there was a highly significant difference in μTBS depending on the IDS strategy (p<0.001). In addition, the interaction of IDS and aging was borderline statistically significant (p=0.045). The specimens failed mainly at the adhesive-dentin interface for all experimental groups. Dentin exposure during clinical procedures for indirect restorations benefits from the application of IDS, which was shown to result in higher bond strength. No significant differences were found between cleaning with solely pumice or pumice followed by tribochemical silica coating.


2020 ◽  
Vol 40 (2) ◽  
pp. 403-423
Author(s):  
Jacob Weinrib

Abstract In Where Our Protection Lies, Dimitrios Kyritsis develops an innovative constitutional framework that aims to reconcile two commitments: democratic governance and the protection of fundamental rights. This review article argues that the reconciliation fails to provide fundamental rights with meaningful protection. On the one hand, the framework’s moral resources hollow out the duties that rights impose on legislatures. Instead of protecting persons from the abusive exercise of legislative power, the framework narrows what constitutes abuse. On the other hand, the framework’s institutional resources leave persons without the means of vindicating their rights. What Kyritsis terms protection consists in the ongoing susceptibility to the violation of one’s fundamental rights.


2004 ◽  
Vol 40 (3) ◽  
pp. 593-635 ◽  
Author(s):  
PIETER A. M. SEUREN

William Croft,Radical Construction Grammar: syntactic theory in typological perspective. New York: Oxford University Press, 2001. Pp. xxviii+416.My reason for writing this review article is that I want to highlight a particular basic opposition in linguistic theory and methodology. On the one hand, we have what is usually called COGNITIVISM, represented in the book under review by the new theory of Radical Construction Grammar, henceforth RCG. On the other hand, there is a variety of schools, together forming a large majority in the field, whose theoretical overlap may be characterized by the term MODULARITY. I argue against cognitivism and in favour of the modularity view, and I am using the book under review as an opportunity to define the issue and put forward the arguments.


2014 ◽  
Vol 535 ◽  
pp. 506-510
Author(s):  
Sakchai Sikka

This is a research in the style of research and development. The researcher conducted fieldwork by collecting data on the current situation of and problems in bamboo-baking in 10 provinces. Then the data were analyzed to find out about the forms of ovens and quality of each type of baking in order to compare the baking quality. Moreover, the data were used in a brainstorm with 12 participators consisting of entrepreneurs and those who are concerned. All the data from the study were used in the determination of the basic requirements for the experiment of designing and creating 4 model ovens. The fourth is the one that has been tested and proved to be suitable for usage in the manufacturing processes of bamboo handicraft, both wickerwork and furniture. In the experiment of preventing the eating of weevils and other insects, it was found that during 6 months, no evidence of such eating was found, which corresponds to the determined standard.


2012 ◽  
Vol 504-506 ◽  
pp. 1177-1182 ◽  
Author(s):  
Fritz Klocke ◽  
David Welling ◽  
Jens Dieckmann ◽  
Drazen Veselovac ◽  
Roberto Perez

This paper deals with developments of Wire-EDM technologies for fir tree slot production. The aim of these developments is to substitute certain conventional processes within turbine manufacturing that have been identified as non-optimal like the critical broaching process. Thereby the negative characteristics like inflexible manufacturing processes, high machine tool investment costs and huge energy consumption can be abolished. The objective targets of the conducted research are to meet all safety requirements of the critical components and get an economic manufacturing process. In the first step a special brass wire technology for cutting Ni-based super alloys was developed. Main focus was to meet the requirements of fir tree production concerning aspects of surface integrity and geometry. To measure these aspects on the one hand non-destructive analyses have been performed to guarantee surface roughness and accuracy. On the other hand destructive analyses in terms of cross section polishing for showing thermal influenced rim zones have been prepared. A capable Wire-EDM process is presented.


2018 ◽  
Vol 1 (2) ◽  
Author(s):  
André Albert ◽  
Wolfgang Zorn ◽  
Markus Layer ◽  
Welf-Guntram Drossel ◽  
Dirk Landgrebe ◽  
...  

The research on lightweight construction increasingly gains in importance, especially for the automotive industry. New lightweight components ensure the necessary stability of car body parts on the one hand. On the other hand they are supposed to allow a low priced production. Hence, aluminum or magnesium alloys have quite a large share in production engineering. During the last years, research mainly addressed metal/plastic compounds. Weight reduction as well as the capability of producing complex structures are only some of the benefits of this technology. Furthermore, additional functionality can be integrated or functional tasks can be distributed: The metal ensures stiffness and realizes the technical connection to the car body by means of welding, while the plastic enables the insertion of special elements for the joining or assembly process. This paper presents two approaches of realizing a combined process to produce aluminum/plastic-hybrid structures. In a first approach, an active tool is presented to realize the sheet based process. The second approach focusses on the tube-based process and presents the topical state of research within the Federal Cluster of Excellence EXC 1075 “Merge Technologies for Multifunctional Lightweight Structures”.


2014 ◽  
Vol 77 (4) ◽  
pp. 317-325
Author(s):  
Lars Albinus

The full doctoral thesis, The Beautiful Thinking, by the DanishHistorian of Ideas Dorthe Jørgensen, is an impressive and erudite workthat challenges modern theology to learn from philosophical aestheticsor, more specifically, a ‘metaphysics of experience’. Taking her point ofdeparture in Baumgarten’s concept of sensitive cognition, she sets out todevelop a philosophy which, contrary to the erratic strictures of empiricalscience, on the one hand, and superficial tendencies of the modern entertainment culture, on the other, is able to grasp experiences of ‘immanenttranscendence’ or ‘a surplus of meaning’. In this review article, however, I warn against the romanticizing implications of this endeavor inasmuch as the subject matter of theology is a confessional tradition rather than some form of experiential sensitivity.


Author(s):  
Jian-Jia Chen ◽  
Joerg Henkel

AbstractResearch and development in the last decades have led to a silicon process that has been expected to become inherently undependable in the near future when migrating towards new technologies. The special priority program (SPP) 1500 funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) in 2010–2016 and the Variability Expedition funded by the National Science Foundation (NSF) in 2010–2015 made a joint effort to explore design challenges of Power Consumption, Reliability, Interference, and Manufacturability under such a design requirement.


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