Information about Electrical Components which contain Lead in a Glass or Ceramic Matrix Compound

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1 Entry 14: Proposal for 2005 components which contain lead in a glass or ceramic matrix Information about which contain Lead in a Glass or Matrix Compound : Lead is today still an essential material for some long-term highly precise passive and active electric / electronic components as well as for piezoceramic based sensors and actuators. These components are often used in automotive applications resulting in a reduction of emissions, noise, weight, less fuel consumption or improved safety systems. From end of life vehicles they will end up in the material recycling processes or on special waste desposal. Amount of lead compared with positive effects for the environment or risk of release is low. For some applications they are the basis to achieve further advanced environmental performance of a car (e.g. to meet standards beyond Euro IV etc.), which is not possible with conventional systems. Meanwhile efforts in research and development of the supplying industry in cooperation with public institutes will be continued to find lead-free alternatives, but these alternatives are not available today. Therefore the automotive industry applies for continuing the existing exemption without any limitation and proposes a review in 2007 /2008.

2 Background information entry 14: : / Annex II (2002/525/EC) Typical Application - Diesel Injection System - Amount / from End of Life Status -free Piezoceramic It is our intention to provide all necessary information to enable a based on fact assessment of the environmental aspect / impact / benefit of lead containing electrical components within automotive applications. Source : Bosch, Epcos, CeramTec, Siemens VDO automotive, FHG

3 Requirements for Electric Containing Lead / Annex II 2002/525/EC Assessment of (PZT) Registered on the List of Exemptions for the Heavy Metal Restriction based on the ELV ( Annex II 2002/525/EC): Entry No. 14: Expire date: Added Obligation: components containing lead in a ceramic matrix none Dismantling for components other than in engines (60 g rule) Ökopol Study II: Heavy Metals in II (Final Report July 2001): p. 35: PZT connected to engine have direct environm. advantages p. 26: Lack of information prevents an overall recommendation Therefore our intension is to provide more detailed information on piezoelectric components With the amendment of the Annex II 2002/525/EC, components containing lead in a glass or ceramic matrix are exempted from the heavy metal restriction of the End of Life Vehicle Directive 2000/53/EC, without fixed expire date. For components other than piezo in engines there is the obligation of dismantling, if together with lead form solder applications an average threshold of 60g per vehicle is exceeded. The Ökopol study on Heavy Metals in II (July 2001) confirms environment advantage of PTZ connected to engine and the necessity of further information. Heavy Metals in II, Ökopol, July 2001:. Besides technical reasons (mainly electrical properties of lead in certain applications) the lack of information plays an important role here." :

4 Lead compounds are used in a glass Matrix for thick-film materials (Circuit carrier) and passive components (resistors, condensers, resonators etc.) Their lead content is mostly below < 5 % and the total amount for a car from this source is below 2g. " components which contain lead are almost exclusively ferroelectric ceramics which belong to the group of piezoelectric materials. In these materials, an electrical voltage is induced when the material is mechanically deformed ("sensor" mode), or on the other hand they undergo a mechanical deformation when an electrical voltage is applied ("actuator" mode)." (Heavy Metals in II, Ökopol, July 2001) The available piezo ceramics are dominated by lead zirconate titanate (PZT). Lead is the main element with a content between 58% and 68% (depending on proportion of Zr to Ti). Lead is still essential in these applications. Although there is intensive research on lead-free alternatives there is no practical alternative today. * The Piezo Effect / Piezoelectric materials: Piezoelectricity is based on the ability of certain crystals to emit an electrical charge when mechanically loaded by pressure or tension (direct piezo effect). Conversely, these crystals undergo a controlled deformation when exposed to an electric field - a behaviour referred to as the inverse piezo effect. The polarity of the charge depends on the orientation of the crystal relative to the direction of the pressure. For automotive applications especially within the engine area piezo-materials with a high Curie temperature and a high level of polarisation saturation are necessary. The best known performance have PZT ceramics, which are a mixture of PbTiO 3 and PbZrO 3. Direct piezoelectric effect means the converting of mechanical quantities such as pressure and acceleration into electrical quantities. Inverse piezoelectric effect means an electric field which induces a mechanical deformation of a piezoelectric crystal.

5 Applications of Piezoceramic within Typical application fields of piezo ceramic components within vehicles Existing application: Engine: Piezo actuator for high pressure direct diesel injection Engine: Knock sensors for engine control Chassis: Shock sensor for airbag Powertrain excl. engine: Rotation rate sensor (gyroscope) for driving dynamics control system Future application: Chassis: Sensors for Active Noise Killing System Chassis: Reversing sensor for park distance control Chassis: Sensor for wheel tyre guard (tyre pressure control) Apart from electric / electronic circuits which contain small components with a low lead content (total amount per vehicle < 2g) there are various applications, either already existing or lying in the future, where Piezoceramic actuators and sensors are the basis for advanced technology. Some of these applications are directly used to optimise the engine performance and so saving fuel and reducing emissions. Even if they serve at first sight only for comfort reasons, they might also generate environmental benefit e.g. active noise killing systems may substitute weight intensive sound insulation materials wheel tyre guards will positively influence running characteristics of a car because they inform the driver about the proper tire pressure and such also reduce fuel consumption park distance control sensors may prevent driving around searching for bigger parking spots. Piezo

6 Typical Application - (1/2) Engine: High pressure diesel injection system (Common Rail) Injector: Injector head with Piezo Actuator Source: Ford The automotive industry has developed a high pressure diesel injection system with piezo technology, the Piezo Common Rail System. A common rail system is an injection system which offers high pressure fuel for injection at any given moment. To get engine noise and emission down it is necessary to add several small pilot- and post-injections to the main injection during a working cycle of a diesel engine. The essential component of the common rail system is the injector. Piezo Cermaic Injection System / The Injector

7 Typical Application - (2/2) Injector head with Piezo Actuator Piezo Actuator Structure of Piezo Multi-layer-Actuator printing pressure passive area The actuation of the injector is the most important parameter in a diesel engine combustion process. The actuation is responsible for injection quantity and time and therefore affects emission, noise and performance of the engine. The injector of the common rail system is designed to reach very low injection quantities. That can be realized exclusively due to a piezo actuated valve which controls the amount of diesel injected. The piezo actuated valve offers the following advantages:

8 Injection System - (1/3) Bytheuseof PiezoActuatorsan optimizedinjectioncontrolcan be achieved due to faster actuator switching times improved response time of the actuation event itself better reproducibility of injection ability to perform variable valve lift The above mentioned characteristics potentiates to perform a multiple injection strategy, which means that several small pilotand post injections are added to the main injection during a working cycle. As a result the engine will be better able to meet exhaust emission regulations much more effectively than with conventional actuators. The valve switches 30 times faster than a conventional solenoid valve, because it requires no time for a magnetic field to be generated and omitted with each reaction. Result: Very low injection quantities and several single injections possible. The piezo actuated valve offers a better reproducibility of the injection quantities than a valve actuated with solenoid technology. Result: Precise injection quantities over the lifetime of a diesel engine which ensures a continuous low level of emission.

9 In practice that means: Injection System - (2/3) The use of Piezo ceramic contributes substantially to meet future emission regulatuons for Diesel and Gasoline engines EURO IV EURO V Only feasible with piezo ceramic! EURO VI Year The Piezo Common Rail System provides the opportunity to meet Euro IV emission standard without additional hardware components on the engine: No particulate filter, no NOx trap, no knock sensor needed. Furthermore Diesel passenger cars equipped with the Piezo Common Rail Systems fulfil Euro IV, which will be introduced 2005 already in The piezo technology offers further potential to meet future emission standards beyond Euro IV, for diesel as well as for gasoline injection systems. Injection System Direct al Advantages

10 Injection System - (3/3) Results of Siemens VDO Diesel emission research activities with Piezo actuated injector and multiple injection strategy (Oct 2003) For complete EUDC 1) : Soot up to -25% NOx up to -25% CO up to -37% HC up to -18% 1) Extra Urban Driving Cycle, specification of EU For urban cycle 2) (low load and speed): CO up to -80% HC up to -55% fuel consumption -4,5% 2) Urban Cycle, specification of EU Additional: noise! This slide shows the impressing reduction of emissions which is possible already with piezoceramic injection systems today. Further research and developments depend also on obligations for dismantling or restriction. Estimation of total Lead Amount for

11 Containing Lead in Glass or Matrix Application Control units Airbag Component Quantity of ceramic (g) Integrated resistor Shock sensor Lead content in ceramic (g) Number per car with... cylinders < 0, ,2 0, Driving dynamics control system Rotation rate sensor 0,08 0, Engine Control High pressure diesel injection Knock sensor Piezo actuator (injector) 5,0 16,6 3,4 11, Total amount of lead per car (g): The total amount of lead for applications for electrical components containing lead in a glass and or ceramic matrix and which are exempted by entry 14 of the Annex II from Heavy Metal Restriction is about 50g up to 100g per vehicle.

12 Positive Effects of Piezo s on Safety or Application of PZT Fuel injection Knock sensor Shock sensor Rotation rate sensor (gyroscope) Active noise killing system Wheel tyre guard Benefit for environment or safety emission fuel consumption Better engine control Safety: activation of airbag Safety: activation of driving dynamic control system Saving of weight intensive acoustic insulation fuel consumption Safety: better vehicle roadholding Piezoceramic used in various applications as well as on the engine as on chassis provides benefits for the environment or safety. al Assessment of a Piezoceramic Diesel Injection System

13 over a total Life-time Diesel Injection System Amount / Considering a kilometric performance of km and an average reduction of emission of 30%: emission ~ 30 4 g Reduced pollution of environment Application of g lead per vehicle in ceramics Is fixed and ends up on special waste deposits Lead content compared with reduction of emission over a vehicle lifetime. Positive effect of Piezo ceramic outbalance the use of g lead. Fate containing Piezoceramics from End of Life

14 (PZT) from End of Life Way of PZT assembled to the engine Way of PZT integrated in the chassis 1) steel smelter, metallurgical processes 2) blast furnace slag 3) special waste deposit 1) shredder light fraction 2) slag of metal recycling or heat recovery 3) special waste deposit Result: Pb release in the is unlikely, because PZT: is chemical largely inert will end up on special waste deposits A release of lead from end of life vehicles into the environment is very unlikely! Lead-free Piezo s

15 Status -free Intensive research on lead-free alternatives, but Highly, durable stability of electronic units over the entire life cycle of a car (resistance variation < 1%) Low temperature coefficient (< 100 ppm/k) Narrow tolerances, especially for safety-related systems (deviation to set value < 1%) Assurance of function under special conditions of a car (temperatures > 130 C; insensivity for humidity, dust, vibrations etc.) Precise, reproducable positioning travel (xµ-range) Required lift of actuator (fast switching time) Realization of high forces (~kn) High curie temperature (ambient temperature of engine ~ 150 C) today only possible with lead Currently it is not possible to substitute lead in piezo ceramic applications!

16 Resarch Efforts al Impact of (PZT) Resarch: BMU (German al Agency) Project together with Industry: Development of lead-free Alternative PZT: Substitution by other Metals (see p. 16) Projects e.g. Siemens CT MM2 Long term Substitution and Avoidance of lead containing Materials and. Development of lead free or lead reduced Piezo s useable for technical applications. There are intensive efforts carried out in the research departments of the supplying industry to develop lead free alternatives. But today technical feasibility is not yet achieved.

17 Exemption for in a Glass or Matrix is still necessary! In small amounts lead is used in glass or ceramic matrix in advanced applications with positive effects on the environment (reduction of emission and fuel consumption) and safety (detection and activation of safety systems). After the lifetime of a vehicle the lead is not released into the environment, but will end up in recycling processes or special waste deposits. Althoug there is intensive resarch activity lead-free alternatives are not yet available. Due to that an exemption for lead in these applications is still neccessary. Therefore the automotive industry applies for continuing the existing exemption without any limitation and proposes next review in 2007 /2008.