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This paper aims to develop build strategies for rapid manufacturing of components of varying complexity with the help of illustration.

The build strategies are developed using a hybrid layered manufacturing (HLM) setup. HLM, an automatic layered manufacturing process for metallic objects, combines the best features of two well-known and economical processes, viz., arc weld-deposition and milling. Depending on the geometric complexity of the object, the deposition and/or finish machining may involve fixed (3-axis) or variable axis (5-axis) kinematics.

Fixed axis (3-axis) kinematics is sufficient to produce components free of undercuts and overhanging features. Manufacture of components with undercuts can be categorized into three methods, viz., those that exploit the inherent overhanging ability, those that involve blinding of the undercuts in the material deposition stage and those that involve variable axis kinematics for aligning the overhang with the deposition direction.

Although developed using the HLM setup, these generic concepts can be used in a variety of metal deposition processes.

This paper describes the methodology for realizing undercut features of varying complexity and also chalks out the procedure for their manufacture with the help of case studies for each approach.

Flash rusting and corrosion undercutting of water‐thinned paint films on iron surfaces are caused by the electrochemical decomposition of that steel surface. Flash rusting is that rust‐coloured spotting which occurs as the iron is solubilized and bleeds through that water‐thinned paint film. The steel simply corrodes because of the flow of electric currents that occur as the pure iron reverts to its more stable compounds: ferric hydroxide, hydrated ferric oxides and ferric oxides. This paper reviews the chemistry of flash rusting and corrosion undercutting and reports on the successful applications of modified barium metaborate in providing both initial and long‐term corrosion resistance for water‐thinned paints on steel. Several physical factors that contribute to flash rusting and corrosion undercutting are also discussed.

The objective of this paper is to develop geometric algorithms and planning strategies to enable the development of a novel hybrid manufacturing process, which combines rapidly re‐configurable mold tooling and multi‐axis machining.

The presented hybrid process combines advantages of both reconfigurable molding and machining processes. The mold's re‐configurability is based on the concept of using an array of discrete pins. By positioning the pins, the reconfigurable molding process allows forming the mold cavity directly from the object's 3D design model, without any human intervention. After a segment of the part is molded using the reconfigurable molding process, a multi‐axis machining operation is used to create accurate parts with better surface finish. Geometric algorithms are developed to decompose the design model into segments based on the part's moldability and machinability. The decomposed features are used for planning the reconfigurable molding and the multi‐axis machining operations.

Computer implementation and illustrative examples are also presented in this paper. The results showed that the developed algorithms enable the proposed hybrid re‐configurable molding and multi‐axis machining process. The developed decomposition and planning algorithms are used for planning the reconfigurable molding and the multi‐axis machining operations. Owing to the decomposition strategy, more geometrically complex parts can be fabricated using the developed hybrid process.

This paper presents geometric analysis and planning to enable the development of a novel hybrid manufacturing process, which combines rapidly re‐configurable mold tooling and multi‐axis machining. It is expected that the proposed hybrid manufacturing process can produce highly customized parts with better surface finish, and part accuracy, with shorter build times, and reduced setup and tooling costs.

The purpose of this paper is to study an electrolytic etching method to prepare fine lines on printed circuit board (PCB). And the influence of organics on the side corrosion protection of PCB fine lines during electrolytic etching is studied in detail.

In this paper, the etching factor of PCB fine lines produced by new method and the traditional method was analyzed by the metallographic microscope. In addition, field emission scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were used to study the inhibition of undercut of the four organometallic corrosion inhibitors with 2,5-dimercapto-1,3,4-thiadiazole, benzotriazole, l-phenylalanine and l-tryptophan in the electrolytic etching process.

The SEM results show that corrosion inhibitors can greatly inhibit undercut of PCB fine lines during electrolytic etching process. XPS results indicate that N and S atoms on corrosion inhibitors can form covalent bonds with copper during electrolytic etching process, which can be adsorbed on sidewall of PCB fine lines to form a dense protective film, thereby inhibiting undercut of PCB fine lines. Quantum chemical calculations show that four corrosion inhibitor molecules tend to be parallel to copper surface and adsorb on copper surface in an optimal form. COMSOL Multiphysics simulation revealed that there is a significant difference in the amount of corrosion inhibitor adsorbed on sidewall of the fine line and the etching area.

As a clean production technology, electrolytic etching method has a good development indicator for the production of high-quality fine lines in PCB industry in the future. And it is of great significance in saving resources and reducing environmental pollution.

The purpose of this paper is to analyse the interaction between a profit maximising mortgagor and a newcomer to a mortgage market with Bertrand competition where the newcomer has a populistic entry strategy and undercuts mortgage market rates. The intention of the paper is to relate the populistic entry strategy to mortgage market characteristics and the strategic market position of both the established mortgagor and the newcomer in question.

The paper analyses a mortgage market by combining the behaviour of a profit maximising mortgagor with that of a newcomer to the mortgage market which has a populistic entry strategy and does not maximise profits. The short-run market solution provides comparative statics on the strategic market position of both the established mortgagor and the newcomer to the mortgage market during the entry phase both related to product differentiation and to price mirroring and undercutting of mortgage rates.

The model finds a mortgage market solution where a lower mortgage rate helps the newcomer gain a customer base. As the newcomer's strategy to mirror prices makes it unable to pass-through funding cost to its mortgage rate, the strategy is unsustainable over time. The established mortgagor has a strategically beneficial position as the mortgage market rates only relate to its funding cost. Unless the newcomer has a funding cost advantage, the established mortgagor has a higher interest rate margin. Differentiation impacts the newcomers’ interest rate margin positively. If the newcomer lacks a funding cost advantage, there is a critical mirroring rate that ensures it a higher interest rate margin. The higher the newcomers’ own funding cost, the higher is the upper bound for price mirroring, relating market entry to a small undercutting of mortgage rates and a mortgage market with weak competition. The funding cost of the established mortgagor pulls pricing in the opposite direction, allowing for a lower mirroring rate and tougher mortgage market competition during entry.

The paper aims to contribute to the understanding of market equilibrium in the absence of profit maximising behaviour. Framing a mortgage market in terms of a duopoly where a newcomer enters with a populistic entry strategy offering a lower mortgage rate and a mortgage product with a different loan-to-value (LTV) ratio, a novel mortgage market case comes about. The populistic entry strategy produces an augmented reaction curve, crucial for the mortgage market rates.

This paper aims to propose a modified full-additive method (MFAM) to fabricate fine copper lines for high density interconnection (HDI) printed circuit boards (PCBs). In addition, the surface of the fine copper lines is treated with a brown oxidation process to obtain good adhesion between the copper and the dielectric resin.

Fine copper lines fabricated by MFAM were observed to evaluate the undercut quality, in comparison to undercut quality of copper lines fabricated by the semi-additive method and the subtractive method. The effect of the thickness of the dry film on the quality of the copper plating was investigated to obtain the regular shape of fine lines. The fine copper lines treated with the brown oxidation process were also examined to generate a coarse surface microstructure to improve the adhesion between the copper and the dielectric resin. The cross section and surface of as-fabricated fine copper lines were characterized using an optical microscope, a scanning electron microscope and an atomic force microscope.

MFAM has the potential to fabricate high-performance fine copper lines for HDI PCBs. Undercut of as-fabricated fine copper lines could be prevented to meet the design requirement of impedance. In addition, fine copper lines exhibit enough adhesive force to laminate with dielectric resin after the brown oxidation process.

MFAM, with the advantages of high efficiency and being a facile process, is developed to fabricate high-quality fine copper lines for industrial HDI PCB manufacture.

The purpose of this paper is to explore an application of computer‐aided design and manufacture (CAD/CAM) to a process of electronically surveying a scanned dental cast as a prior stage to producing a sacrificial pattern for a removable partial denture (RPD) metal alloy framework.

With the introduction of laser scan technology and commercial reverse engineering software, a standard plaster maxillary dental cast with dentition defect was successfully scanned and created as a STL‐formatted digital cast. With the software, the unwanted undercuts were eliminated based on the desired path of insertion. Parts of the RPD framework were then successfully custom‐designed and combined as a whole.

A sacrificial pattern was produced by rapid prototyping (RP) method and finally casted with chromium cobalt alloy. With suitable finishing process, both the sacrificial pattern and the casted framework fitted the cast well.

The research indicated the feasibility of creating a library of RPD framework components. It is believed that, in the future, with the advance of the techniques, a totally new platform can be developed for the design and fabrication of custom‐fit RPD framework based on the CAD/CAM/RP system.

The purpose of this paper is to present a new model to empirically analyze retail pricing dynamics led by the competition between retailers, using fluid milk markets of three US metropolitan areas as a case study. The research is important for Chinese public policy makers to find the reasons of retail price fluctuations and provides policy makers with the direction and rationale to intervene in retailing markets.

This paper empirically applies dynamic oligopolistic competition model using Markov switching regression. The dataset used in this study includes 58 four‐week‐ending observations covering the period from March 1996 to July 2000 for three cities, Boston, Dallas, and Seattle.

The empirical results illustrate the Markov switching regression not only successfully identifies the Markov perfect equilibrium in each market, but decomposes the retail price series into the corresponding equilibrium regimes. The forecasting power of the model is surprising so it can serve as a price monitor of the government. Additionally, the model reveals the different consumer welfare implications given different price regimes. The welfare analysis shows that consumers are most likely to be worse off through price fluctuations, while they are not always better off through a sticky (stable) price series in a market.

The first limitation of the paper is the retail price data is four‐week ending. If a cycle evolves faster within four weeks, the model would overestimate the duration and underestimate the amplitude of cycles. So the study serves as an upper bound of the reality. The second limitation is the number of regimes. More than three regimes studied in a Markov switching regression may cause a series of empirical issues. However, if we integrate several regimes into one regime, we will lose rich information about the competitiveness of the markets.

This paper is the first work to apply the dynamic pricing analysis to food industry by using fluid milk market as a case study. This paper empirically identifies four retail pricing regimes in fluid milk price series and evaluates the characteristics of the regimes.

This paper assesses the welfare implications of each pricing regime. The results show that the forecasting power of the model is strong in fluid milk retail market. Therefore, the study could serve as a price monitor to the public policymaker.

This paper presents the first study to apply dynamic oligopolistic competition model to food marketing research.