Chrome Auto Plating Gains Despite Challenges

A dozen European companies are eyeing increased opportunity to plate injection molded plastic parts as car makers, particularly in Europe and Asia, are stepping up efforts to reduce weight with plastic-for-metal substitutions.

More than 26 interior and exterior parts are plated, particularly in high-end cars even though chromium is a known carcinogen and is listed as a hazardous air pollutant. It provides a mirror-like surface finish, good corrosion resistance and strong aesthetic appeal and substitutes are said to be inferior. Strict environmental rules are in place at plating operations.

The chrome plating process is highly complex and can consist of as many as 30 steps.

Plastic plating (sometimes called galvanizing) is also tricky because any type of surface blemish is magnified. Another challenge is OEM interest in using materials beyond standard ABS, which has been plated for more than 50 years. The butadiene helps in the plating process.

One increasingly used plastic is ABS/polycarbonate T65, which has high PC and low ABS content. Other examples of materials hard to galvanize are 30 percent glass-reinforced polyamide 6 and 50 percent glass-ball reinforced PA6. Sometimes two (2K)- and three (3K)-component moldings are selectively plated. Polyamide blended with 40 percent mineral filler has high tensile strength and is used for special applications such as interior door handles

Use of chromium as a plating agent is said to provide:

  • Excellent corrosion and chemical resistance;
  • Wear and abrasion resistance;
  • Very good adhesion;
  • A high-class surface with mirror-like reflection or aluminum-like matte surfaces; and
  • Hardness, scratch resistance.

Excellent interaction between the injection molding and galvanization processes is required for successful application of the surface finish to materials.

The process starts with etching with a chromic solution to remove the butadiene from the top of the substrate. That creates pits that act as anchor points for the subsequent nickel and other layers. During the electroplating process, chromium  is reduced to metallic chrome.

The European players are Gerhardi Kunststofftechnik GmbH, C. Hübner GmbH, BIA Kunststoff- und Galvanotechnik GmbH & Co KG, Heinze Gruppe GmbH, Bolta Werke GmbH, Boryszew Oberflächentechnik Deutschland GmbH, WAFA Germany GmbH, Aludec Galvanic s.a., C+C Krug GmbH, Fischer GmbH & Co. surface technologies KG, SAXONIA Galvanik GmbH, Karl Simon GmbH & Co. KG. They operate 22 sites in Germany, Spain, Slovakia,  and the Czech Republic.

At least one of the players integrates the process from design and toolmaking through injection molding and electroplating.

Boryszew Oberflächentechnik Deuschland of Prenzlau, Germany currently employs 348 workers and is planning to reach $38 million in sales in 2017. The company’s main market is Germany, but also exports to America and Asia. Boryszew Prenzlau realizes 90 percent of its sales with automotive parts for both interiors and exteriors of vehicles, such as decorative strips or door handles. Its main customer is the VW/Audi group.

Boryszew Oberflächentechnik Deutschland operates 25 injection molding machines with clamping forces ranging from 88 to 785 tons, 13 of which have come from Wittmann Battenfeld. The company also uses the Airmould internal gas pressure technology from Wittmann Battenfeld, since the weight of automotive components plays an important role. Variothermic technology from Wittmann Battenfeld is used for sensitive surfaces.

Injection molded, chrome-plated door handles embedded in a complex assembly. (Wittmann Battenfeld)

ABS, Automotive, Europe, Foam molding, Injection Molding, Molds & Moldmaking, Polyamides, Polycarbonate ,

New Eastman Cellulosic Alloy Targets PC, ABS

Eastman Chemical Co. announced development of an engineering bioplastic breakthrough in a press conference May 15 at Chinaplas.

Eastman Trēva is an interesting material, but the words breakthrough and bioplastic may be more appropriately placed within quotation marks. Its composition is about half cellulose and about half acetic acid and acetic anhydride, which are made from fossil fuels.

Eastman’s Tenite cellulosic plastics, made entirely from wood, were introduced in 1929, and are used in consumer product applications from radios and telephones, to toothbrushes and toys. They are said to have toughness, hardness, strength, surface gloss, clarity, chemical resistance, and “warmth to the touch”.

“Eastman leveraged nearly 100 years of cellulosic expertise in the design and testing of Trēva to meet the improved sustainability profile and performance needs of brands, fabricators, molders, and other companies across the value chain,” said Burt Capel, vice president and general manager of Eastman’s Specialty Plastics business unit.

It targets polycarbonate, PC/ABS, ABS, and acrylic and is described as competitively priced.

Potential applications include:

  • Eyeglass frames, wearable electronics, headphones, and many other personal devices that come in direct contact with the skin;
  • Electronic display applications, such as lenses and covers, that consumers need to see through;
  • Electronics, housings, intricate cosmetics cases, and other products with high design and complex specifications; and
  • Automotive interior components requiring chemical resistance and aesthetics.

“The materials have good clarity, but not the high clarity that you would see with Tritan, PC or acrylic,” says Kevin Duffy, manager of business development, advanced materials – Specialty Plastics at Eastman Chemical. “The transparency for the new Trēva grades is in the low-to-mid 80%’s.  Depending on thickness and optical requirements, this would be OK for many applications.” Some grades of PC are optically transparent.

Trēva’s HDT @ 0.455 Mpa is around 115º C. PC’s HDT ‎at 0.45 MPa: 140° C.

The new Eastman partially sustainable alloy may have an edge in flow, chemical resistance and haptics. It is also BPA free, although it’s not clear if that is significant for non food contact applications.  

It looks like an excellent candidate for niche applications such as eyeglass frames, depending on exact pricing.

New Eastman plastic features good flow, SCR and haptics versus PC. (Eastman Chemical)

ABS, Acrylic, Bioplastics, Consumer Goods, Design, Engineering Thermoplastics, Green, North America, Polycarbonate ,

3D-Printed Lattice Tooling Boosts Productivity

Using a grant from the Walmart Foundation to boost competitiveness of U.S. manufacturing, an Indiana academic research team has developed a new technology to aid in the design of plastic injection molds that can increase productivity, reduce costs, and improve product quality.

The technology uses applied mathematics and software development to optimally design 3D-printed injection molds with functionally graded internal lattice structure (Figure 1). The novel injection mold designs increase cooling efficiency and uniformity around the injected plastic part. The result is faster cooling and reduced stresses in the part, says Dr. Andres Tovar, who is heading up the project at Indiana University-Purdue University Indianapolis (IUPUI).

“The idea of using water flowing through a metal grid to improve cooling is well known, as in a radiator,” says Dr. Tovar. “What we have contributed are the design optimization algorithms that specify the geometry of lattice within the injection mold so that the cooling properties are optimized and the cost of the 3D-printed tool is reduced without compromising strength.”

IUPUI was awarded a $291,202 grant from the Walmart U.S. Manufacturing Innovation Fund in 2014 with the collaboration of the U.S. Conference of Mayors. The project’s goal is to reduce the cost and increase the performance and versatility of U.S.-manufactured plastic injection tooling through experimentally supported, multi-scale, thermo-mechanical topology optimization methods and metal additive manufacturing (3D printing).

The IUPUI research team is comprised of five faculty from the Purdue School of Engineering and Technology: Andres Tovar (principal investigator), Hazim El-Mounayri, Jing Zhang, Doug Acheson, and Razi Nalim. The team currently partners with the additive manufacturing company 3D Parts Manufacturing (Indianapolis, IN). The team has also collaborated with the injection molding company Hewitt Molding Co. (Kokomo, IN).

IUPUI is using a test part provided by Hewitt, a Walmart supplier. The part is a complex cap made from polypropylene. Metal injection molds are now being 3D-printed for an industrial test study that will be conducted this summer to verify the concept. Results will be reported to Walmart and the U.S. injection molding community, in part through the Manufacturers’ Association for Plastics Processors (MAPP).

Dr. Tovar believes the lattice concept of conformal cooling could reduce costs 25 to 30 percent compared to current approaches to conformal cooling using channels through solid structures (Figure 2). Cooling cycle time improvements could be as much as 50 percent above the benefits already provided by traditional conformal cooling. There would also be savings in energy and reduced part waste. He feels the approach would be most useful to applications requiring repeatable tight tolerances.

The IUPUI team is still looking for additional financial partners.

Figure 1. The core plate of an injection mold with conformal cooling and lattice structure: A. Core plate formed by the 3D-printed unit core and frame; B. Metal 3D-printed unit core; C. Cross section of the unit core depicting optimized internal lattice structure. Source: Dr. Tovar’s Laboratory at IUPUI.

Figure 2: Core plate with various cooling systems: A. Traditional straight cooling; B. Conformal cooling; C. Conformal cooling with lattice structure; D. Lattice cooling. Source: Dr. Tovar, IUPUI.

Additive manufacturing, Cooling/Heating, Injection Molding ,

Lego Tests Bricks Made From Wheat Bioplastic

Lego, which uses more than 70,000 metric tons of plastics per year, says it is making progress toward its goal of using only sustainably sourced molding materials.

More than 70 people now work in a new $146 million Sustainable Materials Center headed by Nelleke van der Puil, who was named VP Materials two years ago after she spent 14 years at Advantium, a leading-edge biomaterials company based in the Netherlands.

Wheat-based bricks. (Lego)

Engineers at the center are testing prototypes made of bioplastics to make sure they meet demanding specifications of the global toy maker. Earlier efforts to use specially compounded grades of polylactic acid supplied by NatureWorks fizzled because they lacked long-term “clutch” strength. The PLA worked great, except that complex models would start to collapse after a few weeks because of poor creep properties of PLA.

Newly tested prototypes were made from a plastic derived from wheat. Wheat gluten is a cheap by-product from the bio-ethanol industry that is said to have interesting viscoelastic properties. Lego did not identify the supplier.

“The present materials are carefully selected and refined to perfection over the years regarding their physical properties,” says van der Puil. “These unique properties like strength, durability, clutch power and color fastness makes the building system possible and thereby constitutes the basis for the overall Lego experience. Maintaining these properties in the Lego bricks after a shift to an alternative material, makes the search a real challenge. Maintaining these properties is a prerequisite for the unique Lego play experience.”

Lego is working with many partners, ranging from NatureWorks to startups with embryonic technologies. Last year, the company joined the Bioplastic Feedstock Alliance, an initiative of the World Wide Fund for Nature to help guide the search for sustainable alternatives. Ford and P&G are among the members.

Van der Puil says that Lego is trying to find replacements for more than 20 types of plastics by 2030.

Lego’s criteria for replacement plastics are:

  • No undesirable chemicals;
  • Sustainably sourced and manufactured feedstock; and
  • Minimum waste.

Replacement of fossil fuel plastics is one component of a broad Lego campaign to have a net positive impact on greenhouse gases.

 

ABS, Bioplastics, Consumer Goods, Europe, Injection Molding ,

Sales Rise As SHI Demag Introduces New Line

Sales of injection molding machines at Sumitomo (SHI) Demag Plastics Machinery are rising, but still lag the sales of Demag alone in 2007 before its acquisition by Sumitomo.

The German-Japanese manufacturer of injection molding machinery based in Schwaig, Germany, had sales in 2016 of $254 million, up from $251 million in 2015. The 2016 order rate exceeded sales by 20 percent.

SHI Demag targeted price point and performance with new line of electric machines.

Gerd Liebig, who became CEO in January, attributes the company’s success to sales of the El-Exis machines in the plastics packaging segment and its all-electric IntElect machines among manufacturers of plastic industrial and medical precision parts.

“Over the past two years, our share in the global market for screw caps and thin-wall parts has risen by about 20 percent,” says Liebig. SHI sells more than 5,000 injection molding machines a year and has sold more than 60,000 all-electric injection molding machines.

The company presented a new generation of five IntElect machines with clamping forces between 50 and 181 tons today at the company’s plant in Wiehe, Germany. “The price gap between all-electric and hydraulic machines is closing – with the same range of options and systematic focus on the application,” Liebig said.  The smallest model, which is 1.6 feet shorter than its predecessor, was shown at K2016.

Features of the series include compact footprint, updated motor technology and extended memory capacity for brake energy. SHI claims a savings of 20 percent versus comparable all-electric machines.

At Sumitomo’s headquarters in Chiba, Japan, the company manufactures machines with clamping forces in the small to medium range. Nearly 95 percnet of Sumitomo machines are equipped with all-electric drive.

Demag’s German facilities in Schwaig and Wiehe produce the Systec Servo range with hybrid drive as well as the El-Exis SP and Systec SP range of high-speed, high-performance machines. The all-electric IntElect range for international customers is also being produced in Germany. A new Chinese plant opened two years ago.

Sumitomo Heavy Industries, Ltd. (SHI)  bought Demag Ergotech GmbH of Germany and Van Dorn Demag Corp. of Strongsville, Ohio, from MPM Holdings in 2008. It represented a much-needed consolidation of machinery assets at the time. Demag Ergotech’s sales in 2007 were $272.1 million with gross profit of $61.8 million. Van Dorn closed.

Europe, Injection Molding, Packaging ,

Eastman Develops New Cellulosic Engineering Plastic

Eastman Chemical, a pioneer in the production of cellulosics for more than 100 years, is making its first foray into high-performance engineering bioplastics.

Eastman did pioneering work on cellulosics for use in celluloid film, and also worked on cellulose-based plastics. Tenite acetate, developed in 1929 by Tennessee Eastman, was an early thermoplastic and was used in Craftsman tool handles, toys, sunglass frames, and toothbrush handles. One characteristic is a soft wood-like feel. It’s a plastic made from soft woods, not wood compounded with a thermoplastic like polyethylene. Cellulose is chemically similar to starch.

Cellulosic plastics seem to have been on the decline for at least 60 years as newer, better thermoplastics were developed. They

Until now.

Eastman Chemical announced today that it will introduce a “high-performing engineering bioplastic” based on cellulose at Chinaplas 2017  (May 16-19; China Import & Export Fair Complex, Pazhou, Guangzhou, PR China). No details will be released until the show.

It’s interesting that celluloid movie film—the original moneymaker driving the bus—is virtually dead, but the plastics side of the business still has life.

Bioplastics, Green, North America , ,

3D-Printed Carbon Preforms Are Overmolded In New Technology

Carbon fiber 3D printing and injection molding are integrated in a novel invention from a fast-rising Massachusetts technology startup. The concept targets small, complex parts now made from aluminum and other metals. Applications can range from under-the-hood automotive to jigs and fixtures.

In the concept developed by Markforged, which was formed just four years ago, continuous carbon fiber preforms are 3D printed and are then overmolded with thermoplastic to make strong net-shape parts at a potentially lower cost, lighter weight, and faster production times.

The invention is outlined in a patent application by Markforged founder and CEO Greg Mark that was published yesterday.

Markforged uses it own 3D printer with its patented continuous fiber filament (CFF) technology and its proprietary Eiger software that automatically creates a fiber pattern for “maximum” strength within the 3D print file. Markforged also manufactures continuous fiberglass; Kevlar; and high-strength, high-temperature fiberglass for its printers.

Reinforced plastic parts currently made via injection molding use discontinuous fiber, primarily glass. Use of preforms is limited to low-pressure molding processes, which primarily use thermoset materials.

The new Markforge invention allows high-volume production of very strong parts with a quality surface finish. The pressure of injection forms the preform into a final shape and can be used to dissolve removable thermoplastic preform support structures. The support preform is injection molded as a honeycombed structure with a contiguous outer surface that can be used as a winding substrate. The patent application indicates different ways the support material can be removed.

Two or more continuous fiber reinforcement preforms may be bonded to one another before being placed in the mold. The fiber deposition is an additively deposited thermoplastic continuous fiber reinforced prepreg tape having a width at least three times its height. The reinforcement volume is less than 20 percent of the entire reinforced molding.

The entry price for the company’s Onyx One CFF printer is $3,500. The Mark Two, at a price of $13,500, delivers metal-strength carbon composites for 10 times the strength of plastics, according to the company.  The fiber is in a polyamide matrix. The Mark X industrial-scale printer ($69,000) launched in October of 2016. It features in-process part inspection using a laser micrometer, a larger build size and other precision capabilities.

“Our belief is that every designer and engineer should have broad access to strong, elegant parts from a reliable printer they love to use.” says Greg Mark. “With the Onyx One, we provide our customers with superior parts in a seamless integrated system of hardware, material and software to deliver a quality experience at an accessible price point.”

HOW IT WORKS

Additive manufacturing, Carbon Composites, Design, Insert Molding, North America, Reinforcing Material , ,

Metal Molding Makes Play For Smartphone Covers

Add powder injection molding (PIM) to the list of candidate processes for making smart phone covers stronger and less expensive.

Machine builder Arburg and chemicals’ giant BASF formed a joint venture to develop a material and process to produce housing components for smartphones. The concept was first demonstrated at the World PM2016 Congress and Exhibition, held in Hamburg, Germany last October, and more recently at Arburg’s in-house technology fair in Lossburg, Germany, last month.

“The booming international smartphone market offers huge potential for powder injection molding because this process enables the use of materials such as stainless steel, titanium and zirconium oxide, requires much lower material volumes and is significantly more cost-effective than machining,” says Hartmut Walcher, PIM expert at Arburg,

A hydraulic Allrounder 470 S with a clamping force of 10 tons produced the components from a flow-optimized Catamold 17-4 PH Plus from BASF in Hamburg. A lightly larger press was used in Lossburg. A changeable hot runner mold featuring liquid temperature control was designed to produce a closed or four-part frame. Cycle time is about 55 seconds.

The mold temperature is dynamically controlled to help ensure a constant green density throughout the entire part. The polishable surface finish is described as very good. One goal is to minimize part distortion at a wall thickness of only around 1 mm. Part length is 136 mm.

Arburg has manufactured more than 1,000 PIM machines in the past 50 years.

Powder injection molding is a method to mass produce net shape metal or ceramic parts. Powders are mixed with a polymer binder so the material will flow into an injection mold. Parts are first injection molded (called green), and then the binder is removed and parts are “baked” in a sintering oven to remove pores created by the binder.

Photo shows the gripper tool for the mobile phone frame. (Arburg)

 

Automation/Robotics, Design, Electronics, Europe, Metal Injection Molding, Metal Injection Molding (MIM) , ,

PlastiComp Expands Proprietary CFRP Compounding

PlastiComp, a compounder in Winona, Minnesota, is boosting capacity of an interesting, proprietary process to make long-fiber, carbon-reinforced plastic (CFRP) pellets.

The additional, higher-volume carbon fiber pultrusion line will triple PlastiComp’s capacity for producing long carbon fiber products. “In recent years we have experienced continuous growth in demand for our long carbon fiber reinforced composite materials,” said Eric Wollan, vice president and chief operating officer at PlastiComp. 

The firm brought its initial production line dedicated to producing long carbon fiber composite pellets online in 2014 and operates four other pultrusion lines to manufacture its long glass fiber products.

The pultrusion process used to make long fiber pellets for injection molding processing is different from the standard thermoset pultrusion process used to make lineal shapes such as ladders. Continuous fiber roving/tow (glass, carbon, or other) is pulled through a pressure die where the fiber tow is spread and melt impregnated with thermoplastic polymer. A compounding extruder operates as a melt pump to feed the molten polymer into the die.

Composite strands exit the die and are cooled into thin composite rods, which we cut into 12 mm (one half inch) pellets to facilitate material handling. If pellets are too long, they clog up the feed throat of the injection molding machine.

 PlastiComp makes its own equipment other than the melt pump extruder and the pelletizer

Carbon fiber composites are manufactured by PlastiComp on pultrusion lines located in self-contained areas equipped with isolated electrical and air handling systems.

“From a pultrusion perspective, carbon fiber’s small filament diameter and conductivity makes it a little more challenging to manufacture composite pellets than other types of fiber,” said Wollan.  “Using our specialized equipment, PlastiComp is able to completely melt impregnate continuous tows of carbon fiber with 12,000 to 50,000 filaments.”

Plasticomp says that long carbon fiber reinforced thermoplastic composites provide the strongest and stiffest performance available in flowable materials suitable for injection molding processing.  PlastiComp’s Complēt pellets contain 15 to 50 percent (by weight) long carbon fiber in thermoplastic matrices ranging from polypropylene to PEEK.

CFRPs offer mechanical performance equivalent to aluminum while providing design-dependent weight reductions up to 50 percent.

Thermoplastic materials incorporating carbon fiber reinforcement are conductive (<10E5 ohms-per-square), providing surface and volume resistivity properties and up to 80 decibels (dB) of shielding effectiveness against electromagnetic interference.

The firm also has a long fiber composites line that combines glass fiber and carbon fiber together into a single pellet.

Carbon fiber loaded on spolls feeds into new pultrusion line. (Plsticomp)

Carbon Composites, Carbon Fiber, Glass-Reinforced Composites, North America, PEEK, polypropylene

Toshiba Machine Gets Divorce From Toshiba; Expands Line

Toshiba Machine Co., Tokyo, has extracted itself from the troubled Toshiba Group, and is expanding its lineup of injection molding machinery.

The company is launching the all-electric EC280SXII, featuring a clamping force of 2,744 kN (280 metric tons), and the EC350SXII, featuring a clamping force of 3,430 kN (350 metric tons). They will both be made in China and target a specific application: precision molding of automobile optical parts.

“The EC-SXII series features a wide of array of packages for optical parts such as automobile LED headlight lenses, in-car lighting and displays, and more, for contributing to higher productivity and more stable precision molding,” said Masafumi Ito of the Regional Operating Headquarters (East Asia).

Last month, Toshiba Machine Co. bought back a controlling amount of stock owned by Toshiba Corp. “As a result, they are no longer our top shareholder and we no longer belong to the Toshiba Group,” said Toshiba Machine Chairman and CEO Yukio Iimura at the company’s North American headquarters in Elk Grove Village, Illinois.

Toshiba Machine took the action due to customer concerns about the Toshiba Group’s financial stability in the wake of significant losses in the company’s nuclear power business operated by Westinghouse.

According to Iimura, the transition for Toshiba Machine has been seamless, with no impact to its operations, customers, shareholders, employees or business partners.

Westinghouse field for bankruptcy March 24 because of billions of dollars of cost overruns at four nuclear reactors under construction in the U.S. Southeast. Toshiba shares lost half their value since the nuclear problems became public late last year. The problems also began to affect Toshiba Machine, although it was only 21 percent owned by Toshiba Group.

Toshiba Machine was established in 1938 as a heavy machine tool manufacturer, and has evolved into a diverse business comprised of approximately 48 regional companies and offices supplying global markets with injection molding machines, machine tools, die-casting machines, extruders, robotics and high-precision machines. The company says it has an installation base of more than 60,000 injection molding machines worldwide, owns all of the buildings in which it operates, and employs more than 3300 worldwide.

Toshiba Machine is boosting clamping force of its all-electric injection molding machines with two new models. (Toshiba Machine)

Asia, Automotive, Injection Molding ,