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This paper aims to predict tool wear and reveal the relationship between feed per tooth and tool wear in micro-milling Inconel 718 process.

To study and solve the tool wear problem in micro-milling of Inconel 718 micro components, in this paper, the investigation of micro-milling Inconel 718 process was implemented based on DEFORM finite element simulation, and tool wear depth of micro-milling cutter acted as output.

Different from the traditional macro milling process, diameter reduction percentage and average flank wear length decreased with the increase of feed per tooth; tool wear depth decreased when the feed per tooth was less than the minimum chip thickness.

At present, research on the prediction of tool wear in micro-milling of Inconel 718 has never been publicly reported. This study is significant to reveal the relationship between cutting parameters (feed per tooth) and tool wear in micro-milling Inconel 718.

The Deutscher Verband für Schweisstechnik (German Welding Society) made a very judicious and much appreciated choice of venue for its Third International Conference on 18–20 February, 1986, on Interconnection Technology in Electronics. Fellbach, less than 10 km from the Schlossplatz in Stuttgart, and whose past profile was shaped almost entirely by winegrowing, has become since the opening in 1976 of the Schwabenlandhalle a town renowned equally for its significance as a conference centre. With the vine‐crowned Kappelberg hill dominating the town and commanding views to the Neckar Valley, Swabian hospitality and friendliness at its best, and a most impressive congress hall with excellent facilities in picturesque snow‐clad surroundings, the ingredients for providing a conference venue conducive to an optimum interchange of technological information were certainly present.

“This article is mainly concerned with swarf produced by machine tools using neat cutting oils. If the factory has no means of extracting the oil from this, anything from 40 to 80 gal/ton swarf will be carried away on the scrap dealer's lorry. But it can be a messy and uneconomic proposition if no thought is given to it”.

Kelp is widely productive and inexpensive. The purpose of this study is to explore kelp liquid (KL) as an environment-friendly water-based lubricant, which is expected to replace some industrial lubricants and protect the environment while satisfying lubricating performance.

In this experiment, the soaked kelp was broken up by a wall-breaking machine to get the KL by a centrifuge. Elements and crystal structure of KL samples were characterized by X-ray photoelectron spectroscopy, X-ray diffraction and Raman spectra. The friction test is carried out by the relative movement of the polyethylene ball and the aluminum disk on the friction tester.

Friction experiments showed that 0.1 Wt.% KL has a good lubrication effect, and the average coefficient of friction is 0.063 under the condition of applying a 10 N load and moving at a speed of 2.0 cm/s. KL has good thermal conductivity with excellent cooling effect and high intermolecular force which makes high viscosity for excellent lubricating behavior, at the meantime molecules in solution remain stable which shows an excellent dispersibility.

At present, the research on kelp mainly focuses on its medicinal value and abundant nutritional value, and the research on its lubrication effect is less. Based on this situation, this paper explored the characteristics of KL as an environmentally friendly lubricant, which is expected to be used as a green cutting fluid.

This paper aims to compare visual (Munsell) and instrumental (CIELAB) attributes of SCOTDIC colour standards.

SCOTDIC cotton and polyester standards of defined hue, value and chroma were subjected to spectrophotometric assessment for finding the corresponding instrumental parameters. The visual and instrumental parameters were compared.

The correlation between SCOTDIC value and CIELAB lightness is quite high. Correlation coefficient between SCOTDIC hue and CIELAB hue angle and the correlation between SCOTDIC chroma and CIELAB chroma were only moderate because the CIELAB chroma varied widely at higher chroma. When the standards of SCOTDIC hues having erratic hue angles at two extremes are excluded, the Correlation coefficients between SCOTDIC hue and CIELAB hue angle become high.

The psychophysical data (visual) are difficult to match with physical data (instrumental).

The object of the present research is to study and compare visual (Munsell) and instrumental (CIELAB) colorimetric parameters. Munsell scale is physically exemplified by SCOTDIC fabric samples available in two sets, namely, cotton and polyester sets.

Attempts to reveal some of the factors that might cause measurement and evaluation errors in dry sliding. Discusses matters such us “what” and “how” is simulated and “why” and “what” is really measured and suggests ways to tackle these matters. Presents means of avoiding measurement errors as well as suitable testing procedures. Suggests a strategy of experimental work that encompasses the needs of both pure research and engineering design. It was found that the pin‐on‐disc test largely satisfies the conditions for a good simulation of certain engineering applications while providing a wealth of data for both scientific insight and engineering design.

The paper aims to investigate tool wear mechanism and tool geometry optimization of drilling PCB fixture hole.

An experimental study was carried out to investigate the chip formation and tool wear mechanism of drilling PCB fixture holes. Two types of drill with different types of chip-split groove were used in this study. The performances of these two types of drill bots were evaluated by tool wear and the shapes of chips.

The chips of drilling fixture holes contain aluminum chips from the cover board, copper chips from the copper foil, discontinuous glass fiber and resin from the CFRP. Feed rate and drilling speed have a great influence on the chip morphology. Abrasive wear of the drill lip is the main reason of the fixture drill bit in drilling PCB, and micro-chipping is observed on the tool nose and chisel edge. The influence of distance between the chip-split groove and drill point center on the axial force and torque is not obvious.

In this paper, hole wall roughness and drilling temperature were not analyzed in the optimization of drilling parameters. The future research work should consider them.

This paper investigated the mechanism of burr formation and tool wear in drilling of PCB fixture holes. Tool geometry was optimized by adding chip-split grooves.

The purpose of the study was to discover whether incorporating flours with high nutritive value along with pre-treatment of cereals with nixtamalization and sprouting of legumes would result in a high-quality healthy alternative for corn-based snacks.

Flours of nixtamalized cereals-corn, wheat, rice and sorghum and sprouted legumes-soybean and green gram are made into dough and baked instead of fried to form multi-grain chips. The particle size and physical properties of flour and nutritional, functional and textural properties of dough and chips are tested to study the effect of combination of nixtamalization of cereals and sprouting of legumes in the development of chips.

Baked multi-grain chips made of nixtamalized cereals and sprouted legumes had a significantly (p < 0.05) smaller particle size of 24.6 µm compared to T1 24.8 µm, C1 29.3 µm and C2 31.7 µm. T2 and C2 had significantly (p = 0.05) lower OAC value than C1 and T1 due to nixtamalization as nixtamalized flour needed half the amount of oil during dough formation. T1 showed highest calcium (mg/100 g) of 466 which was significantly (p < 0.05) higher than all other groups. The overall acceptability of T2 (8.6) was significantly (p < 0.05) higher than T1 (7.8), C2 (7.4) and C1 (6.8) on the nine-point Hedonic scale.

The developed chips are superior in terms of higher protein and minerals with better organoleptic acceptability and lower fat content in comparison to both corn chips and nixtamalized corn chips. The multi-grain chip therefore offers a new option for the consumer in high-quality healthy alternative to corn-based fried snacks.

The transferred carbon nanofibers (CNFs) can be applied in flip chip package as interconnect material, as an alternative to the conventional solder and conductive adhesive (CA) materials.

The structure of CNFs was confirmed by transmission electron microscopy (TEM). The electrical performance of the vertically aligned carbon nanofibers (VACNFs) joint was measured by four points probe method and compared to conventional lead‐free solder Sn3.0Ag0.5Cu, pure indium and silver CA. A shear test was carried out in order to evaluate the mechanical performance of VACNFs joint. After the shear test, the fracture surface was analyzed by scanning electron microscopy and energy dispersive spectroscopy (SEM‐EDS).

The results showed a high success rate in the transfer of VACNFs from growth chip to target chip. The Au‐coated CNF can be wetted well with melted indium during the transfer and bonding process. In‐Au intermetallic compound (IMC) formed on the surface of CNF. The electrical and mechanical performance of VACNFs is comparable to that of the traditional interconnect materials. The fracture surface is located at the interface between VACNFs and chips. The stacked‐cone structure of CNF can be confirmed from a cross‐section of the break CNF by TEM.

Ultra‐short VACNFs were grown and first successfully transferred to the target chip using a process which required little pressure, low temperature and short time.

The purpose of this paper is to examine electrical and mechanical properties of radio frequency identification (RFID) chip joints assembled on a flexible substrate and made from isotropic conductive adhesives (ICAs) reinforced with graphene nanoplatelets (GPNs) or graphite nanofibers (GFNs).

The ICAs reinforced with GPNs or GFNs were prepared and screen printed on a test pattern to investigate resistance and thickness of these adhesive layers. Differential Scanning Calorimetry (DSC) was performed to assess a curing behaviour of the prepared ICAs. Then, RFID chips were mounted with the prepared ICAs to the pattern of silver tracks prepared on foil. Shear test was carried out to evaluate mechanical durability of the created chip joints, and resistance measurements were carried out to evaluate electrical properties of the tested ICAs.

The 0.5 per cent (by weight) addition of GFNs or GPNs to the ICA improved shear force values of the assembled RFID chip joints, whereas resistance of these modified adhesives increased. The DSC analysis showed that a processing temperature of the tested adhesives may range from 80 to 170°C with different curing times. It revealed a crucial influence of curing time and temperature on electrical and mechanical properties of the tested chip joints. When the chip pads were cured for too long (i.e. 60 minutes), it resulted in a resistance increase and shear force decrease of the chip joints. In turn, the increase of curing temperature from 80 to 120°C entailed improvement of electrical and mechanical properties of the assembled chips. It was also found that a failure location changed from the chip – adhesive interface towards the adhesive – substrate one when the curing temperature and time were increased.

Further investigations are required to examine changes thoroughly in the adhesive reinforced with GFNs after a growth of curing time. It could also be worth studying electrical and mechanical properties of the conductive adhesive with a different amount of GFNs or GPNs.

The tested conductive adhesive reinforced with GFNs or GPNs can be applied in the production of RFID tags because it may enhance the mechanical properties of tags fabricated on flexible substrates.

Influence of GFNs and GPNs on the electrical and mechanical properties of commercial ICAs was investigated. These properties were also examined depending on a curing time and temperature. New conductive materials were proposed and tested for a chip assembly process in fabrication of RFID tags on flexible substrates.