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1-Magnaplate : (lubrication technique)

New(better)

Magnaplate developed several process techniques for bonding dry lubricant coatings to space metals. The magnaplate applied coatings offered enhanced surface hardness and superior resistance to corrosion and wear.

Magnaplate applied synergistic coatings are used in wide spectrum of applications ranging from pizza making to laser manufacture.

Magnaplate enhanced composite coatings are created in multistep process. After the base metal is cleaned, it is thermally sprayed with engineered layers of ceramic particles. Then the layered ceramic matrix is infused with engineered polymers or other dry lubrication particles to create a dense. Structurally integrated nonporous surface. This technique says magnaplate surpasses conventional spray coating and provides aharder than steel, permanently dry lubricated surface with superior corrosion resistance, wear resistance and easier mold release.

(J. J. Haggerty, NASA Spinoff, 1994, p.106)

Old:

Magnaplate:

Magnaplate coatings are a series of multistep, proprietary processes that become an integral part of the top layer of the base metal. Each coating series serves a particular purpose by protecting a specific metal or group of metals. Most coating series can be further adapted to solve specific problems. 

The process begins with a through cleaning of the parts, followed by a deposition of an intermediate high-density film or by thermal spraying, depending on the coating. The process continues with a controlled infusion of selected polymers or other dry lubricating particles. These particles are then mechanically cross-linked and locked in by a proprietary process to become a permanent, integral part of the newly enhanced surface layer.

Magnaplate series of coatings: Tufram, Nedox, Plasmadize, Hi-T-Lube, Lectrofluor, Canadize, Magnaplate HMF, Magnaplate HCR, Magnadize, Magnagold, Magnaplate TCHC, Magnaplate SNS

(James Brown, Advanced Machining Technology Handbook, Page 427-431)

2-Valisys programming (software programming)

New:better

The lack of standard has lead to the development by software companies such as valisys(technomatix) and Dassault systems of their own way to representing and implementing GD&T in CAD.

In valisys, the softgauge is a mathematical description of a GD&T tolerance zone and its datums. This fully three dimentional representation of a tolerance zone for a geometrical feature can be highligted and viewed in the CAD system and used for tolerance analysis,CMM programming and evalation of CMM data.

(Mackay R., changing the ways we work, p.586)

Old:

One of the dynamic software suppliers is the Valisys Corporation which was

formed in November 1987 after a few years of development work. Since then, the company has

been developing and supporting manufacturing automation software products that validate part

designs, use design data to automate inspection processes and support quality control analysis.

 The first decision of the Valisys development team was that a universal desigh language had

to be used to allow design information from various geographical sites to be exchanged. The task

was simplified because of the universal acceptance of the ANSI standart which describes geometric

dimensioning and tolerancing. The symbols used in GDET provide labels for engineering drawings

that not only provide dimensions, but also indicate functional relationships and other characteristics.

This standart code prevents misinterpretations.

 At this time, it is useful to restate the main problem confronting computer integrated

manufacturing. it is the difficulty communicating engineering data from product designers to

manufacturing engineering to the shop floor. Now, the Valisys Corporation' s software, which is

one of the modern manufacturing software systems that improves the flow and accuracy of the

engineering data in a manufacturing environment, will be described.

(Modern Manufacturing Processes, James A. Brown, pg. 177)

3-Electrochemical Superfinishing (surface process)

Old:better

Conventional superfinishing by vibration grinding is a microfinishing operation in which the surface mirco-irregularities are removed by the continuous and slow reciprocation of abrasive sticks that move along the workpiece length. The sticks oscillate concurrently with short and rapid strokes with a continuously revolving workpiece. This process is however known to sustain some of the surface microirregularities such as waviness and out of roundness. In electrochemical superfinishing (ECS), the combination of electrolytic dissolution (ECD) and mechanical scrubbing (MS) improves the performance of the conventional superfinishing process. As a result of such a combination, the dissolution process assists the small stock removal rate due to the mechanical chipping action. Higher stock removal rates become achievable using either a separate cathodic tool electrode, or a diamond abrasive stick with a metallic bond. The high stock removal capabilities combined with the ability to generate close dimensions gave high merits to the ECS process in all fields of industry. The need for initial grinding, which is required before conventional superfinishing, is avoided. ECS can be used when other processes fail to yield high removal rates or generate the required size in difficult-to-machine alloys as well as tool steel. Applying ECS to parts that are susceptible to heat and distortion is advantageous because the bulk of the metal is removed electrochemically in an electrolyte-cooled atmosphere. The problem of thermal distortion, normally found in conventional superfinishing, is therefore eliminated. Burr-free components can also be obtained as a result of the ECD process.

(Advanced Machining Processes, Hassan El-Hofy; Page:192)

New:

This material-removal process employs electrolysis to dissolve a metal workpiece. The dissolution is caused by an exchange of charges and materials between the workpiece, produced as anode, and the tool, produced as cathode, under theforce of electric currentin an electrolyte that serves as the effective medium.

(Menges G. ,how to make injection molds, p.63)

4-Hard Milling (surface process)

old

Throughout the last few years, hard milling has captured the attention of manufacturers around the world. These manufacturers are typically focused on the mold and die industry where materials such as P20, H13, W5, S7, and others are commonly cut. Traditionally, core and cavities from these materials are manufactured in the hardened state using electrical-discharge machining. Through the years, new technologies have been developed where these materials can be, in most cases, machined directly into hardened material using new toolpath processing techniques to form hard milling. These materials can range from 45 HRC to as hard as 64 HRC. Advanced moldmakers have realized that adopting new technology can be one of their keys to survival against global competition.

Digital drives that can handle fast acceleration/deceleration provide good contouring accuracy while helping to minimize cutting-tool wear. Spindles should provide flexibility, offering high torque at low speeds and high power over a large speed range.

Mold shops use three general types of hard milling tools: solid carbide endmills, indexable carbide inserts, and, most recently, ceramic indexable inserts. Each of these tools has its strengths and weaknesses depending upon the application. Solid carbide endmills are usually precision ground, coated, and quite expensive. The second type of hard milling tool is a cutter with indexable carbide inserts. In most cases the carbide grades and geometry of these inserts are not designed well for hard milling, and they do not offer optimal tool life or productivity in hardened materials.

The third type is ceramic indexable inserts, more specifically, whisker-reinforced ceramic inserts.The benefits of using a system of cutters with indexable ceramic inserts include faster cycle times and a reduced number of operations per part. A full line of cutters for hard milling with whisker-reinforced ceramics enables a shop to rough out a part from a solid hardened block – including face milling, pocketing and profiling with indexable inserts – and finish it in one setup.

(Davim J. P.,Machining of Hard Materials, 2011, p. 17-18)

New:

Nowadays, heat treated workpieces may be finished to final strength by millling. Various operations e.g. cavity sinking by EDM, can be replaced by complete milling operations and the process chain thus shortened. Furthermore the thermal damage to the outher zone that would otherwise result from erosion does not occur. Hard milling can be used both with conventional cutting tool materials, such as hard metals, and with cubic boron nitride.  

(Menges G. ,how to make injection molds, p.54)