Primary focus areasPrimary focus areas

Materials – composition and strength

Heat treatmentResidual stressDie coatings & surface treatments

H-13

June 7, 2000 Residual Stress June 7, 2000 Residual Stress ReportReport

Residual stress Task Residual stress Task Force GoalsForce Goals

Develop means to reduce the softening effect during production cycling to improve die life

Develop means to Reduce build-up of residual stresses that contribute to premature failure

Residual stress taskforce Residual stress taskforce Facilitators & participantsFacilitators & participants

Case western reserve university Ast – American stress technologies Pace industries Intermet – Ganton Ford motor company General motors powertrain Badger Metal Tech, Inc.

Residual stress task forceResidual stress task force

approachapproach Develop baseline stress data Must Perform on Production dies Measure with x-ray diffraction and

Barkhausen readings Repeat until stress cracking

initiates Determine threshold values to

indicate when maintenance or corrective action is needed

Current Test Site Current Test Site Pace Industries Pace Industries

MOMOgm – cav 9,10gm – cav 9,10

high volume runner multiple cavities flat surface prone to h/c history of rapid h/c flexible production schedule smaller size inserts for handling reasonable time frame for results approval of end user

Cavity #9

Photos taken during Pace visit

ShotBiscuit

Die Sampled350 SHOTS

Approximate area where X-ray and Barkhausen

measurementsare being taken

Directions#1 0 degrees# 2 -45 degrees# 3 -90 degrees

Prior to 1Prior to 1stst #9 #9

Cavity #10

REAR RETAINERPhotos taken during Pace visit

ShotBiscuit

Die Sampled350 SHOTS

Directions#1 0 degrees# 2 -45 degrees# 3 -90 degrees

Approximate area where X-ray and Barkhausen

measurementsare being taken

Prior to 1Prior to 1stst #10 #10

Residual stressResidual stressfirst measurementfirst measurement

(Die already sampled - 350 (Die already sampled - 350 shots)shots)

Procedure Measurements taken by AST at specified

areas determined by past history and Case Western recommendations

Die X-ray site plotted for future measurements

Barkhausen readings in same locations Inserts returned to Pace for

approximately 20-30K shots Repeat measuring cycle for stress and

Barkhausen readings until steel upsets & heat checking occurs

Second Measurement

Die had 20,523 shots (producing castings (03/29/2000)

(Will attempt to pull every 20-30K- takes 2 weeks)

AST commented that, upon receipt, noted that the calibration area selected on the dies for the 1st measurement appeared to be aggressively ground.

Same reference point used for measurement #1 would make Barkhausen readings (which measures change) not usable.

New calibration piece for reference was made by AST but not from (H-13).

Measurements taken and returned to Pace.

third Measurement Die has 41,209 shots 04-25-00 Measurements taken and returned

to Pace on 05-03-2000.

Trend is Increasing toward zero for Xrd – More compressive ????

decreasing for the bna.

Not what was expected

No physical signs of upset as yet

Date Shots X-Ray (XRD in KSI) Barkhausen (BNA numerical)Measured 0 degrees -45 degrees -90 degrees 0 degrees -45 degrees -90 degrees

Part Cav #9FIRST READ 02/17/2000 350 +33.3 +/- 2.6 +34.8 +/- 1.8 +41.2 +/- 1.6 80.1 97.6 173.3

SECOND 03/14/2000 20,523 +29.3 +/- 1.8 +38.7 +/- 2.1 +50.7 +/- 1.4 52.9* 54.9* 98.4*THIRD 05/02/2000 41,209 + 8.1 +/- 1.9 +17.3 +/- 2.6 +22.7 +/- 2.3 41 40 56

TREND

Part Cav #10FIRST READ 02/17/2000 350 +35.7 +/- 1.6 +40.1 +/- 1.6 +41.0 +/_ 1.2 44.5 81.4 80

SECOND 03/14/2000 20,523 +38.9 +/- 1.8 +59.8 +/- 1.1 +63.9 +/- 1.5 32.4* 64.8* 69*THIRD 05/02/2000 41,209 +28.0 +/- 1.7 +41.7 +/- 1.8 +53.7 +/-1.5 22 40 48

TREND

* The calibration area selected on the dies during run 1 of testing was aggressively ground when the dies .arrived for round #2. A separate calibration piece (not H-13) was created during round 2 that will be kept at AST.

Sensor Units for Barkhausen were same as first time.(Round #2 dies were ground in area where we took reference barkhausen readings)[Barkhausen measures changes - ie: Residual Stresss, Hardness, Micro-structureand outputs it as a numerical value.

Current readingsCurrent readings

trend indicates decreasing tensile stress

InstrumentationInstrumentationInstrumentationInstrumentation

Central UnitCentral UnitCentral UnitCentral UnitSensorSensorSensorSensor

MagnetizeMagnetize

Amplify and Amplify and FilterFilter

ApplyApplyMagnetic Magnetic

FieldField

Detect Detect B-signalB-signalDisplay and Display and

OutputOutput

Barkhausen NoiseBarkhausen Noise

Principle of TestingPrinciple of TestingPrinciple of TestingPrinciple of TestingMagnetizing Magnetizing VoltageVoltageMagnetizing Magnetizing VoltageVoltage

SteeSteellSteeSteell

SensoSensorrSensoSensorr

Central UnitCentral UnitCentral UnitCentral UnitTestTestAreAreaa

TestTestAreAreaa

Barkhausen NoiseBarkhausen Noise

Effect of StressEffect of StressEffect of StressEffect of Stress

LowLowAmplitudeAmplitudeLowLowAmplitudeAmplitude

HighHighAmplitudeAmplitudeHighHighAmplitudeAmplitude

CompressionCompressionCompressionCompression

TensionTensionTensionTension

Amplitude Amplitude StressStress

Amplitude Amplitude StressStress

AmplitudeAmplitudeAmplitudeAmplitude

AA22AA22

AA11AA11

StressStressStressStress

Barkhausen NoiseBarkhausen Noise

Effect of HardnessEffect of HardnessEffect of HardnessEffect of Hardness

LowLowAmplitudeAmplitudeLowLowAmplitudeAmplitude

HighHighAmplitudeAmplitudeHighHighAmplitudeAmplitude

High HardnessHigh HardnessHigh HardnessHigh Hardness

Low HardnessLow HardnessLow HardnessLow Hardness

AmplitudeAmplitudeAmplitudeAmplitude

Amplitude Amplitude HardnessHardness

Amplitude Amplitude HardnessHardness

HardnessHardnessHardnessHardnessRRccRRcc

AA22AA22

Barkhausen NoiseBarkhausen Noise

Recommended and Recommended and Approved for Use byApproved for Use byRecommended and Recommended and

Approved for Use byApproved for Use by SAE - Society of SAE - Society of

automotive automotive

engineeringengineering Department of the Air Department of the Air

ForceForce FAA - Federal Aviation FAA - Federal Aviation

AdministrationAdministration

SAE - Society of SAE - Society of automotive automotive

engineeringengineering Department of the Air Department of the Air

ForceForce FAA - Federal Aviation FAA - Federal Aviation

AdministrationAdministration

Future testing & Future testing & studiesstudies

Continue testing cav #9 & #10Intermet (Ganton) – measure a

four cavity die for ford

Next phaseMetalife, dynablueSurface treatment combinationsVarious coatings – pvd & cvd