Material Group | P - Steel |
Sub-Group | Low Carbon Steel |
Tensile Strength | 720-950 [N/mm^2] |
Machinability | 55% - 80% |
20AP steel, a proprietary case-hardening steel from Carpenter Technology, offers a combination of good core strength, toughness, and surface hardenability. While its alloying elements contribute to its desirable mechanical properties, they also present certain challenges during machining that require careful consideration.
Understanding the Machinability of 20AP Steel:
Composition: 20AP typically contains around 0.18-0.23% carbon, 0.70-1.00% manganese, 0.15-0.35% silicon, and 0.90-1.15% chromium. These elements enhance its strength, hardenability, and wear resistance. However, they can also increase its hardness, especially after heat treatment, potentially leading to challenges like increased tool wear, chip welding, and difficulties in achieving desired surface finishes.
Applications: 20AP is commonly used for gears, shafts, pinions, and other components requiring high surface hardness and wear resistance coupled with good core toughness.
Overcoming Machinability Challenges:
Tool Selection: Choose cutting tools specifically designed for alloy steels or case-hardening materials. Carbide tools with appropriate coatings, such as TiAlN or AlTiN, can enhance tool life and cutting performance in machining 20AP steel. Consider using cermet or ceramic inserts for improved performance in hardened conditions.
Cutting Parameters: Adjust cutting speeds and feeds based on the specific heat treatment and hardness of the 20AP steel. Generally, moderate cutting speeds are recommended for the core material, while lower speeds and increased feed rates are preferred for the hardened case.
Coolant/Lubricant: Utilize a suitable coolant or lubricant to reduce heat, friction, and chip welding during machining. Water-based coolants or cutting oils with additives for improved lubricity are often recommended for alloy steels like 20AP.
Chip Control: Employ chipbreakers or specialized tool geometries to promote chip breaking and prevent long, stringy chips that can interfere with the machining process and potentially damage the workpiece or tool.
Additional Tips for Machining 20AP Steel:
By understanding the unique characteristics of 20AP steel and implementing these strategies, machinists can effectively manage its machining challenges and achieve desired results in terms of productivity, tool life, and surface finish.
For detailed carbide grade and cutting speed recommendations, refer to resources like the material supplier's datasheet (Carpenter Technology) or consult with a machining expert familiar with alloy steels.
Steel 20AP, a proprietary steel from Carpenter Technology, has no direct equivalent international designations. However, based on its properties and applications, there are some comparable materials you might consider:
Potential European Equivalents
EN 1.2714 (20MnCr5): This case-hardening steel offers similar hardenability and core strength to 20AP. It is commonly used for gears, shafts, and other components requiring high surface hardness and wear resistance.
EN 1.2311 (16MnCr5): This steel also exhibits good hardenability and core strength. It is suitable for applications requiring good toughness and fatigue resistance.
EN 1.2312 (20MnCr5): This steel is another case-hardening option with slightly higher manganese content than 1.2714. It offers similar properties but might provide slightly improved hardenability.
Other International Equivalents:
Important Considerations:
While these steels share some similarities with 20AP, it's important to remember that they are not exact equivalents. The specific chemical composition, heat treatment, and mechanical properties may differ. Therefore, it's crucial to consult with a materials expert or refer to the material specifications to determine the most suitable alternative for your specific application.
Element | Amount |
---|---|
Manganese (Mn) | 0.25-0.50% |
Carbon (C) | 1% |
Sulfur (S) | 0.045% |
Phosphorus (P) | 0.035% |
Silicon (Si) | 0.3% |
Application | Vc (m/min) | Vc (SFM) |
---|---|---|
Turning | 240-350 | 790-1150 |
Milling | 150-220 | 490-720 |
Parting | 115-170 | 380-560 |
Grooving | 135-195 | 440-640 |
Drilling | 95-140 | 310-460 |
While machining guidelines for 20AP steel offer a valuable starting point, optimizing your cutting speeds necessitates understanding the factors impacting its machining performance. Remember, estimations are based on ideal conditions, which aren't always replicated in real-world scenarios.
Factors Affecting Cutting Speed in 20AP Steel:
Carbide Grade: Choosing the right grade is key. Although 20AP is a free-machining steel, its specific grade selection should consider the desired surface finish, tool life, and whether you're machining the core or hardened case. For the core, grades suitable for low-alloy steels might suffice. However, for the hardened case, tougher substrates and wear-resistant coatings (e.g., TiAlN, AlTiN) or even cermet/ceramic inserts may be necessary.
Tool and Workpiece Clamping: Secure and rigid clamping of both the cutting tool and workpiece is fundamental. Any vibrations or movement can negatively impact accuracy, surface finish, and tool life. Employ proper clamping techniques and utilize high-quality tooling systems to mitigate these risks. This is crucial for 20AP, especially when machining its hardened case.
Raw Material Quality: Variations in raw material quality, encompassing chemical composition, heat treatment, and microstructure, can significantly affect machinability. Source high-quality 20AP steel from reputable suppliers and verify its properties to ensure consistent and predictable machining performance.
Tool Overhang: A shorter tool overhang minimizes deflection and vibration, leading to improved cutting stability and surface finish. Strive for the shortest possible overhang without compromising tool reach and accessibility. This is particularly important for 20AP, often used for long, thin components where deflection can be a concern.
Material Hardness: The hardness of the 20AP steel workpiece directly impacts cutting forces and tool wear. Verify that the material's hardness falls within the expected range for the chosen carbide grade and cutting parameters. Adjust cutting parameters, particularly reducing speed and increasing feed, to accommodate the hardened case.
Additional Factors:
By meticulously evaluating these factors and adjusting cutting speeds accordingly, you can fine-tune your machining process to achieve superior results when working with 20AP steel. Remember, the recommended cutting speeds are a guideline, and real-world optimization requires a holistic approach that considers the entire machining ecosystem.
Disclaimer: The information provided here is intended as a general guideline. It is crucial to consult with tooling experts, refer to manufacturer recommendations (especially from Carpenter Technology for 20AP), and conduct thorough testing to determine the optimal cutting parameters for your specific application and the specific properties of your 20AP steel.
Grade | Coating | Apps Range | 05 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 |
---|---|---|---|---|---|---|---|---|---|---|---|
SHARP METAL | |||||||||||
YP15T | PVD & CVD | P15 | |||||||||
PM25 | PVD TiAlN | P20 | |||||||||
NC25 | PVD TiAlN | P20 | |||||||||
TN15 | PVD TiAlN | P20 | |||||||||
TN20 | PVD TiAlN | P20 | |||||||||
TIN25 | PVD TiAlN | P20 | |||||||||
YP25T | PVD & CVD | P25 | |||||||||
YP35T | PVD & CVD | P35 | |||||||||
FM CARBIDE | |||||||||||
FM2533 | CVD | P10 - P10 | |||||||||
FM2543 | CVD | P20 | |||||||||
FM324 | PVD | P20-P30 | |||||||||
FM2553 | CVD | P30 | |||||||||
CANELA | |||||||||||
NC25 | CVD | P05 - P20 | |||||||||
TN15 | CVD | P10 - P25 | |||||||||
TN20 | CVD | P20 - P25 | |||||||||
PM25 | Uncoated | P20 - P35 | |||||||||
TIN25 | PVD | P20 - P35 | |||||||||
PM40 | Uncoated | P35 - P45 | |||||||||
TN30 | CVD | P40 | |||||||||
TL20 | PVD | P20 | |||||||||
KM15 | Uncoated | P15 | |||||||||
ISCAR | |||||||||||
IC807 (IC907) | PVD | P05 - P25 | |||||||||
IC8150 | CVD | P10-P15 | |||||||||
IC8250 | CVD | P15-P30 | |||||||||
IC830 (IC328) | PVD | P25 - P45 | |||||||||
Seco | |||||||||||
TH1500 | CVD | P05 - P05 | |||||||||
TP0501 | CVD | P05 - P20 | |||||||||
TP1501 | CVD | P10 - P25 | |||||||||
TP2501 | CVD | P15 - P35 | |||||||||
CP500 | PVD | P15 - P40 | |||||||||
CP600 | PVD | P25 - P45 | |||||||||
TP3501 | CVD | P30 - P40 | |||||||||
KENNAMETAL | |||||||||||
KCP05B (KCP05) | CVD | P05 - P10 | |||||||||
KCP10B (KCP10) | CVD | P10 - P20 | |||||||||
KCU10 (KC5010) | PVD | P10-P20 | |||||||||
KCP25B (KCP25) | CVD | P20 - P30 | |||||||||
KCU25 (KC5025) | PVD | P20-P30 | |||||||||
KCP30 | CVD | P30-P40 | |||||||||
KCP40B (KCP40) | CVD | P35 - P45 | |||||||||
SANDVIK | |||||||||||
GC1115 | PVD | P05 - P20 | |||||||||
GC4305 | CVD | P05 - P10 | |||||||||
GC4415 (GC4315) | CVD | P10 - P15 | |||||||||
GC4425 (GC4325) | CVD | P15 - P30 | |||||||||
GC1125 | PVD | P20 - P30 | |||||||||
GC4335 | CVD | P30-P40 | |||||||||
TUNGALOY | |||||||||||
T9205 (T9105) | CVD | P05 - P10 | |||||||||
T9215 (T9115) | CVD | P10 - P20 | |||||||||
AH725 | PVD | P15 - P30 | |||||||||
T9225 (T9125) | CVD | P15 - P25 | |||||||||
T9235 (T9135) | CVD | P30 - P40 | |||||||||
WALTER | |||||||||||
WPP10S (WPP10) | CVD | P05 - P20 | |||||||||
WPP05S (WPP05) | CVD | P05 - P15 | |||||||||
WPP20S (WPP20) | CVD | P10 - P30 | |||||||||
WPP30S (WPP30) | CVD | P20 - P40 | |||||||||
MITSUBISHI | |||||||||||
UE6105 | CVD | P05 - P15 | |||||||||
MC6015 (UE6010) | CVD | P10 - P20 | |||||||||
VP15TF | PVD | P10 - P30 | |||||||||
MC6025 (UE6020) | CVD | P15 - P20 | |||||||||
MC6035 (UE6035) | CVD | P25 - P40 | |||||||||
SUMITOMO | |||||||||||
AC8015P (AC810P) | CVD | P05 - P15 | |||||||||
AC8020P | CVD | P10 - P25 | |||||||||
AC1030U | PVD | P10 - P30 | |||||||||
AC8025P (AC820P) | CVD | P15 - P30 | |||||||||
AC8035P (AC830P) | CVD | P25 - P45 | |||||||||
KYOCERA | |||||||||||
PR1005 | PVD | P15 | |||||||||
PR930 | PVD | P15-P25 | |||||||||
PR1115 | PVD | P15-P25 | |||||||||
PR1535 | PVD | P25 | |||||||||
PR1025 | PVD | P15-P35 | |||||||||
PR1225 | PVD | P15-P35 | |||||||||
PR1425 | PVD | P15-P35 | |||||||||
PR1532 | PVD | P35 | |||||||||
PR1625 | PVD | P35 | |||||||||
IP2000 | PVD | P25 | |||||||||
IP3000 | PVD | P35 | |||||||||
1001 | CVD TiCN | P10 | |||||||||
3010 | CVD TiCN | P20 | |||||||||
3030 | CVD TiCN | P30 | |||||||||
3030 | PVD | P35 | |||||||||
801 | PVD TiAlN | P15-P30 | |||||||||
3020 | CVD TiCN | P20-P30 | |||||||||
PC8105 | PVD | P15 | |||||||||
PC8110 | PVD | P15 | |||||||||
PC8115 | PVD | P25 | |||||||||
PC5300 | PVD | P25-P35 | |||||||||
YBG101 | PVD | P15 | |||||||||
YBG102 | PVD | P15 | |||||||||
YBG105 | PVD | P15 | |||||||||
YB9320 | PVD | P25 | |||||||||
YBG205 | PVD | P25 | |||||||||
YBG202 | PVD | P25 | |||||||||
YBG302 | PVD | P35 |
Grade | Coating | Apps Range | 05 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 |
---|---|---|---|---|---|---|---|---|---|---|---|---|
FM CARBIDE | ||||||||||||
FM125 | PVD | P20-P30 | ||||||||||
FM199 | PVD | P30 | ||||||||||
CANELA | ||||||||||||
PM25 | Uncoated | P25 | ||||||||||
PM40 | Uncoated | P40 | ||||||||||
SANDVIK | ||||||||||||
GC1125 | PVD | P05 - P20 | ||||||||||
GC1135 | CVD | P15 - P35 | ||||||||||
ISCAR | ||||||||||||
IC808 (IC908) | PVD | P05 - P30 | ||||||||||
IC830 (IC328) | PVD | P20-P40 | ||||||||||
SECO | ||||||||||||
TGP45 | CVD | P10 - P45 | ||||||||||
CP500 | PVD | P20 - P45 | ||||||||||
T350M | CVD | P25 - P45 | ||||||||||
CP600 | PVD | P30 - P50 | ||||||||||
KENNAMETAL | ||||||||||||
KCU10 | PVD | P05 - P20 | ||||||||||
KCU25 | PVD | P20 - P30 | ||||||||||
WALTER | ||||||||||||
WKP13S | CVD | P05 - P20 | ||||||||||
WSM23S | PVD | P10 - P30 | ||||||||||
WSM33S (WSM33) | PVD | P20-P40 | ||||||||||
WSM43S | PVD | P30 - P45 | ||||||||||
SUMITOMO | ||||||||||||
AC1030U (AC530U) | PVD | P10 - P25 | ||||||||||
AC520U | PVD | P15 - P30 | ||||||||||
AC830P | CVD | P20 - P40 | ||||||||||
TUNGALOY | ||||||||||||
AH725 | PVD | P15 - P30 | ||||||||||
AH7025 | PVD | P20 - P30 | ||||||||||
GH130 | PVD | P25 - P40 | ||||||||||
MITSUBISHI | ||||||||||||
VP10RT | PVD | P05 - P10 | ||||||||||
VP20RT | PVD | P10 - P30 | ||||||||||
VP15TF | PVD | P10 - P30 |
Grade | Coating | Apps Range | 05 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
FM CARBIDE | ||||||||||||||||||||||
FM90 | DLC | P20 | ||||||||||||||||||||
FM20 | Uncoated | P10 | ||||||||||||||||||||
CANELA | ||||||||||||||||||||||
PM25 | Uncoated | P25 | ||||||||||||||||||||
PM40 | Uncoated | P40 | ||||||||||||||||||||
SANDVIK | ||||||||||||||||||||||
GC1125 | PVD | P05 - P35 | ||||||||||||||||||||
ISCAR | ||||||||||||||||||||||
IC807 (IC907) | PVD | P05 - P10 | ||||||||||||||||||||
IC808 (IC908) | PVD | P10 - P25 | ||||||||||||||||||||
IC830 (IC328) | PVD | P20 - P40 | ||||||||||||||||||||
KENNAMETAL | ||||||||||||||||||||||
KC5010 | PVD | P10 - P20 | ||||||||||||||||||||
KCU10 | PVD | P10 - P20 | ||||||||||||||||||||
KC5025 | PVD | P20 - P30 | ||||||||||||||||||||
KCU25 | PVD | P20 - P30 | ||||||||||||||||||||
WALTER | ||||||||||||||||||||||
WKP13S | CVD | P05 - P20 | ||||||||||||||||||||
WSM23S | PVD | P10 - P30 | ||||||||||||||||||||
WSM33S (WSM33) | PVD | P20-P40 | ||||||||||||||||||||
WSM43S | PVD | P30 - P45 | ||||||||||||||||||||
SECO | ||||||||||||||||||||||
CP500 | PVD | P10 - P25 | ||||||||||||||||||||
CP600 | PVD | P20 - P40 | ||||||||||||||||||||
TUNGALOY | ||||||||||||||||||||||
T9225 (T9125) | CVD | P15 - P25 | ||||||||||||||||||||
AH725 | PVD | P15 - P30 | ||||||||||||||||||||
AH7025 | PVD | P20 - P40 | ||||||||||||||||||||
GH130 | PVD | P25 - P40 | ||||||||||||||||||||
MITSUBISHI | ||||||||||||||||||||||
VP10RT | PVD | P05 - P10 | ||||||||||||||||||||
VP20RT | PVD | P10 - P25 | ||||||||||||||||||||
MY5015 | CVD | P10 - P20 | ||||||||||||||||||||
VP30RT | PVD | P20 - P40 | ||||||||||||||||||||
SUMITOMO | ||||||||||||||||||||||
AC1030U (AC530U) | PVD | P10 - P25 | ||||||||||||||||||||
AC520U | PVD | P15 - P30 | ||||||||||||||||||||
AC830P | CVD | P20 - P40 |
Grade | Coating | Apps Range | 05 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 |
---|---|---|---|---|---|---|---|---|---|---|---|
FM CARBIDE | |||||||||||
FM125 | PVD | P15 - P35 | |||||||||
CANELA | |||||||||||
PM25 | Uncoated | P05 | |||||||||
PM40 | Uncoated | P05 | |||||||||
TL10 | PVD & CVD | P05 | |||||||||
TL20 | PVD & CVD | P05 | |||||||||
TL40 | PVD & CVD | P05 | |||||||||
TIN21 | PVD & CVD | P05 | |||||||||
TIN25 | PVD & CVD | P05 | |||||||||
SANDVIK | |||||||||||
GC4330 | CVD | P10 - P25 | |||||||||
GC4340 | CVD | P25 - P40 | |||||||||
ISCAR | |||||||||||
IC808 (IC908) | PVD | P05 - P15 | |||||||||
IC830 (IC928) | PVD | P10 - P40 | |||||||||
KENNAMETAL | |||||||||||
KC510M | PVD | P05 - P10 | |||||||||
KC522M | PVD | P10 - P25 | |||||||||
KCPK30 | CVD | P25 - P40 | |||||||||
KC725M | PVD | P30 - P40 | |||||||||
WALTER | |||||||||||
WKP25S (WKP25) | CVD | P15 - P35 | |||||||||
WKP35G | CVD | P25 - P45 | |||||||||
WSM45X | CVD | P35 - P45 | |||||||||
WSP45S (WSP45S) | PVD | P35 - P45 | |||||||||
SECO | |||||||||||
MP1501 | CVD | P05 - P20 | |||||||||
F40M | PVD | P05 - P50 | |||||||||
MP2501 | CVD | P15 - P45 | |||||||||
TUNGALOY | |||||||||||
AH120 | PVD | P15 - P25 | |||||||||
AH725 | PVD | P15 - P30 | |||||||||
AH3225 | PVD | P20 - P35 | |||||||||
T3225 | CVD | P20 - P35 | |||||||||
AH130 | PVD | P25 - P40 | |||||||||
AH3135 | PVD | P30 - P40 | |||||||||
MITSUBISHI | |||||||||||
MP6120 | PVD | P10 - P30 | |||||||||
MP6130 | PVD | P20 - P40 | |||||||||
VP30RT | PVD | P25 - P45 | |||||||||
SUMITOMO | |||||||||||
ACP2000 | CVD | P05 - P25 | |||||||||
XCU2500 | CVD | P05 - P30 | |||||||||
ACU2500 | PVD | P10 - P40 | |||||||||
ACP3000 | PVD | P20 - P45 | |||||||||
SHARP METAL | |||||||||||
DP20M | PVD TiAlN | P15-P25 | |||||||||
DP30M | PVD TiAlN | P30-P35 | |||||||||
DP40M | PVD | P40 | |||||||||
KYOCERA | |||||||||||
PR830 | PVD | P20 | |||||||||
PR1225 | PVD | P20 | |||||||||
PR1230 | PVD | P20-P30 | |||||||||
PR1525 | PVD | P20-P340 | |||||||||
FM CARBIDE | |||||||||||
CY9020 | PVD | P20 | |||||||||
JP4120 | PVD | P20 | |||||||||
CY150 | PVD | P20 | |||||||||
JS4045 | PVD | P30 | |||||||||
CY250 | PVD | P30 | |||||||||
CY250V | PVD | P30 | |||||||||
CY25 | PVD | P30 | |||||||||
HC844 | PVD | P30 | |||||||||
JS4060 | PVD | P40 | |||||||||
PTH30E | PVD | P40 | |||||||||
PTH40H | PVD | P40 | |||||||||
JX1060 | PVD | P40 | |||||||||
YG-1 | |||||||||||
602 | PVD TiAlN | P15-P30 | |||||||||
PRAMET | |||||||||||
M8310 | PVD | P20 | |||||||||
8215 | PVD | P20 | |||||||||
2003 | PVD | P20 | |||||||||
M8325 | PVD | P30 | |||||||||
M8326 | PVD | P30 | |||||||||
M8330 | PVD | P30 | |||||||||
M8340 | PVD | P40 | |||||||||
M8345 | PVD | P40 | |||||||||
M8346 | PVD | P40 | |||||||||
KORLOY | |||||||||||
PC3600 | PVD | P20-P30 | |||||||||
PC3500 | PVD | P30 | |||||||||
PC3700 | PVD | P30 | |||||||||
PC5400 | PVD | P40 | |||||||||
ZCC | |||||||||||
YBG102 | PVD | P20 | |||||||||
YBG202 | PVD | P20 | |||||||||
YBG252 | PVD | P20 | |||||||||
YBG302 | PVD | P30 |
Honing Siz | 0.05-0.08 mm / 0.002-0.003" |
Rake Angl | 11° -13° |
Land Angl | Positive |
Land Widt | 0.20-0.30 mm / 0.008-0.012" |