MITSUBISHI MATERIALSCopper & Copper Alloy Business

MITSUBISHI MATERIALSCopper & Copper Alloy Business

Japanese

Products information

GloBrass
ECO BRASSLead-free brass with excellent machinability

GloBrass
ECO BRASS
Applicable to RoHS directive, ELV directive and Tap water quality standards
Standard No.
ECO BRASS
JIS
C6931, C6932, CAC804
CDA
C69300, C69310, C87850, C87870
EN
CW724R, CB768S, CC768S
GloBrass
CDA
C68370

GloBrass and ECO BRASS are environmentally friendly materials, complying with RoHS directive, ELV directive and Tap water quality standards.

GloBrass is the new material whose copper content is close to general brass, the machinability and the strength are well balanced, it is possible to supply thinner bars, so it is recommended to mass-market segment which lead-containing brass are applied.

ECO BRASS is suitable substitutes for lead-containing brass as well as Austenitic stainless steel (SUS304), since ECO BRASS has a similar strength to stainless steel in addition to characteristics like superior machinability and hydrogen embrittlement resistance.

GloBrass, ECO BRASS

RoHS directive, ELV directive, Tap water quality standards (Drinking water quality standards)

GloBrass and ECO BRASS contain lead less than 0.09%, complying with RoHS directive, ELV directive and Tap water quality standards, especially NSF61 (Lead elution amount : 5ppb) of Tap water quality standard in the U.S.
Material properties of GloBrass and ECO BRASS are improved by containing Si which does not affect to health while Lead does harm to.

Enforcement Area Name of Regulation Field Outline of the Regulation
April 2003 JP Ministry of Health, Labor and Welfare Ordinance No. 43 of 2002 tap water Allowable lead content in tap water was reduced from 0.05mg/L to 0.01mg/L (about 10 ppb).
April 2011 US NSF14 tap water This regulation is related to dezincification corrosion resistance and stress corrosion cracking resistance.
July 2012 US NSF61 tap water Allowable amount of lead dissolved into water was reduced from 15 ppb to 5 ppb.
Jan. 2014 US S3874 tap water The amount of lead contained in plumbing fittings is restricted (weighted average: 0.25%).
Dec. 2017 EU ELV Directive automobile Lead may be contained at 0.1% or less (extension of the exemption allowing inclusion of up to 4.0% lead in a copper alloy has been approved).
May 2018 EU RoHS Directive electronics Lead may be contained at 0.1% or less (extension of the exemption allowing inclusion of up to 4.0% lead in a copper alloy has been approved).
Jan. 2021 EU Drinking Water Directive tap water Allowable amount of lead dissolved into tap water was reduced from 10 ppb to 5 ppb.
Sep. 2022 AU NSF372 tap water The amount of lead contained in plumbing fittings is restricted (weighted average: 0.25%). - - - Transitional period: 3 years
Feb. 2023 US AB100 (a Californian bill a.k.a. Chan Bill) tap water Allowable amount of lead dissolved into tap water was reduced from 5 ppb to 1ppb. - - - Provisional
Jan. 2024 US NSF61 tap water Allowable amount of lead dissolved into tap water was reduced from 5 ppb to 1ppb. - - - Provisional

Trend in Environmental Regulations

Use of a material containing a harmful substance such as lead, marcury, cadmium, or hexavalent chromium for an electrical or electronic component or an automotive component is prohibited by RoHS Directive and ELV Directive.
However, due to an exemption temporarily applied, copper alloys are still allowed to contain up to 4% Pb.
The Consultants of these Directives proposed extension of the exemptions until 2024 in November 2021 with respect to the ELV Directive, and until July 2026 in December 2021 with respect to the RoHS Directive respectively.
The Consultants also indicated that the subjects to which the exemptions are applicable should be more specific and limited in the next review.
Note: The latest information is available on OEKO's website.
Carl-Otto Gensch. Öko-Institut e.V. :"RoHS Evaluations" (https://rohs.exemptions.oeko.info/).

Global Material

ECO BRASS®️ is the world best-selling lead-free, free-cutting brass.
The alloy's accumulated global sales volume reached 300,000 tons in 2019.

Application, Positioning

GloBrass is the new material whose copper content is close to general brass, the machinability and the strength are well balanced, it is possible to supply thinner bars, so it is recommended to mass-market segment which lead-containing brass are applied.

ECO BRASS series are ECO BRASS, SnECO and ECO-CR, SnECO is superior for erosion resistance*1, ECO-CR is outstanding for corrosion resistance*2. Each brass is applied to Automotive parts, Electrical parts and Faucet parts etc.

Proposal for application

Faucet parts etc. : Water meter case, Faucet fittings, Sprinkler head
Automotive parts : Solenoid valves, Turbocharger bearings, Brake parts, Relief valve, Temperature sensor, Insert nuts, Tire valves
Electrical parts : 2-3 way valves / Flare nuts / Terminals for Air conditioners
Watch parts : Watch crowns, Case

Type Corrosion resistance Erosion resistance Application
Faucet parts Automotive parts Electrical parts
GloBrass Average Average Average Good Good
ECO BRASS Good Good Good Good Good
SnECO Good Excellent Excellent
(Fast flow)
- -
ECO-CR Excellent Good Excellent - -
Lead-containing brass, C3604 Average Average Average Good Good
*1 Erosion resistance : Resistance to erosion due to physical action of high-speed fluid
*2 Corrosion resistance : Resistance to chemical corrosion

Features

Each Characteristic of GloBrass and ECO BRASS is as follows.
Various Characteristics of GloBrass are superior to Lead-containing brass, the electrical conductivity of GloBrass is higher than Phosphor bronze,
it is applicable for terminals which transfer electric signals.
ECO BRASS series has well balanced performance and similar strength to Austenitic stainless steel (SUS304).

Type Tensile strength Wear resistance Corrosion resistance Machinability Forgeability Castability Electrical
conductivity
(%IACS)
GloBrass Good Good Average Good Excellent Good 16
ECO BRASS Good Good Good Good Good Good 8
SnECO Good Good Excellent Good Good Good 8
ECO-CR Good Good Excellent Good Good Good 8
Lead-containing brass, C3604 Average Average Average Good - - 26
Lead-containing brass, C3771 Average Average Average Good Good - 27
Austenitic stainless steel (SUS304) Good Excellent Good Average Average - 2

Chemical composition, Standard number of ECO BRASS series

Chemical compositions and Registered Standard number are as follows.

(Weight %)

Type Shape Standard number Cu Si P Sn Pb*1 Cd*1 Zn
CDA JIS EN
ECO BRASS Bar C69300 C6932 CW724R 75.5 3.0 0.08 <0.1 <0.09 <0.0075 Rem.*2
Casting C87850 CAC804 CB768S 76.0 3.0 0.08 <0.1 <0.09 <0.0075 Rem.*2
SnECO Bar C69310 C6931 - 76.0 3.0 0.08 0.5 <0.09 <0.0075 Rem.*2
Casting C87870 CAC804 - 76.0 3.0 0.08 0.5 <0.09 <0.0075 Rem.*2
ECO-CR Bar - - CW724R 76.3 3.2 0.09 0.2 <0.09 <0.0075 Rem.*2
GloBrass Bar C68370 - - 62.5 1.0 0.07 <0.2 <0.1 <0.0075 Rem.*2
*1 RoHS・ELV directive value Pb≦0.1     Cd≦0.01
*2 Including inevitable impurities and trace additive elements

Shape

GloBrass and ECO BRASS are supplied as following shapes.

 
Bar, Rod
Forged products
Ingot for casting
Continuous casting rod
Continuous casting tube
GloBrass Available Available Available - -
ECO BRASS Available Available Available Available Available
SnECO Available Available Available Available Available
ECO-CR Available Available Available - -

Physical properties

Physical properties are as follows.

Typical values

Property GloBrass ECOBRASS Lead-containing brass
C3604
Bronze-casting
CAC406
Specific Gravity
g/cm3
8.3 8.3 8.5 8.8
Thermal Conductivity
W/m・K
73 35 114 70
Electrical Conductivity
%IACS
16 8 26 15
Coefficient of Thermal Expansion
×10-6/℃
19 20 21 18
Liquidus temperature
880 890 900 1010
Solidus temperature
865 855 885 860

Mechanical properties (Sampling direction : L.D.)

Mechanical properties are as follows.

Bar, Rod Typical value for Φ20mm
Property GloBrass ECO BRASS Lead-containing brass
C3604
Stainless steel
SUS304
Tensile Strength
MPa
625 650 435 660
0.2% Yield Strength
MPa
470 420 295 310
Elongation
%
20 20 25 55
Hardness
HV
(185) (200) (140) (160)
Casting Representative value
Property ECO BRASS Bronze-casting
CAC406
Tensile Strength
MPa
400 220
0.2% Yield Strength
MPa
170 -
Elongation
%
20 15

Machinability of GloBrass, ECO BRASS

The chips of C3604 are cut off because of stress concentration on Pb particles which are soft and low melting temperature.
On the other hand, the chips of GloBrass are cut off due to stress concentration on β phase. The chips of ECO BRASS are cut off because of stress concentration on κ・γ phases which are hard.

GloBrass and ECO BRASS are applicable for dry cutting, because it's Lead-free. If the chips are not cut off under the same cutting conditions of C3604, we suggest that higher feed rate and lower cutting speed could be effective.
Furthermore, if breakage of cutting edge occurs, cutting edge with honing (small radius) could be one of the solution, such as recommended tools for stainless steel.

Mechanism of the machinability
 
GloBrass
ECO BRASS
Lead-containing brass
C3604
Metal structure
Chips
Cutting conditions : Dry cutting, Cutting speed 40m/min, Depth of cut 1.0mm, Feed rate 0.1mm/rev, Corner radius 0.4mm

Example of Turning, Drilling, Tapping, Threading and Cutting-off

One of the test results is as follows, it was possible to machine GloBrass, ECO BRASS under the same cutting conditions as Lead-containing brass C3604.
The cycle time of GloBrass and ECO BRASS was shorter than that of Austenitic stainless steel (SUS303) because of the higher cutting speed and feed rate.
The video is as follows. (https://youtu.be/X2Ie3rsLKu0)

Example of Turning, Drilling, Tapping, Threading and Cutting-off

Part after machining Φ20mm Bar (GloBrass)

Part after machining Φ20mm Bar (GloBrass)
Cutting conditions
Process Cutting tools* GloBrass, ECO BRASS
C3604
(Dry cutting)
Austenitic stainless steel
SUS303
(Wet cutting)
Holder Insert Rev.
(min-1)
Cutting speed
(m/min)
Feed rate
(mm/rev)
Rev.
(min-1)
Cutting speed
(m/min)
Feed rate
(mm/rev)
1 Facing SDJCR1212M11 DCMT11T304-LM
(VP15TF)
2122 120 0.1 1768 100 0.1
2 Leading-drill DLE1000S100P090 - 2785 70 0.07 1194 30 0.05
3 Drilling MVS0800X05S080 - 3183 80 0.1 2387 60 0.1
4 Turning SDJCR1212M11 DCMT11T304-LM
(VP15TF)
1989 100 0.1 1592 80 0.1
5 Threading MMTER1212H16-C MMT16ERG60-S
(VP15TF)
700 - 2 700 - 2
6 Turning SDJCR1212M11 DCMT11T304-LM
(VP15TF)
1768 100 0.1 1415 80 0.1
7 Cutting-off GYSR1212JX00-D13 GY2M0200D020N-GS
(VP20RT)
2000 - 0.1 2000 - 0.1
* MITSUBISHI MATERIALS supplies Cutting tools.(http://www.mitsubishicarbide.com/en/)

Hot Forging of GloBrass, ECO BRASS

The deformation resistance of GloBrass is lower than Lead-containing brass C3771, so any cracks did not occurred.
GloBrass has well forgeability, the proper temperature is 580~650℃. However, C3771 cracked below 620℃ and at 820℃.
On the other hand, suitable temperature of ECO BRASS is 700~760℃, in which the deformation resistance is low.

Hot Forging of GloBrass, ECO BRASS
The samples after hot forging
hot forging graph

Wear resistance of GloBrass, ECO BRASS

Wear amount of GloBrass or ECO BRASS is smaller than C3604 during the Amsler wear test with the lubrication.

Lubrication conditions :
Silicon oil,
Dripping and oil bath

Dezincification corrosion resistance of ECO BRASS

ECO BRASS shows excellence in Dezincification corrosion resistance, because ECO BRASS contains little Zn, and no low β phase in terms of electrochemical in the matrix.

Stress corrosion cracking resistance of ECO BRASS

ECO BRASS has superiority in stress cracking resistance, since its composition of low Zn and 3% Si improves effectively for the performance.

Erosion Corrosion resistance of SnECO

Wear amount of SnECO is lower than C3604, and similar to CAC406(Bronze), because addition of Sn is effective for the corrosion resistance.

Jet stream test

Corrosion resistance of ECO-CR

ECO-CR has the best corrosion resistance in ECO BRASS series, ECO-CR is recommended for localized corrosion of normal ECO BRASS.

C3604
ECO-CR

ISO6509 : Dezincification corrosion test

Inquiry

Environment Product Sales Group, Extruded Product & Wire Rod Sales Dept.

TEL:+81-6-6355-5101

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