[et_pb_section fb_built=”1″ _builder_version=”4.16″ global_colors_info=”{}”][et_pb_row _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/www.secowarwick.com\/wp-content\/uploads\/2024\/04\/Retort-furnace-for-gas-nitriding-process-ZeroFlow.jpg” alt=”Retort furnace for gas nitriding process \u2013 ZeroFlow\u00ae
\n” title_text=”Retort furnace for gas nitriding process – ZeroFlow\u00ae” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.23.1″ global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ admin_label=”section” _builder_version=”4.16″ custom_padding=”25px|||” transparent_background=”off” make_fullwidth=”off” use_custom_width=”off” width_unit=”on” global_colors_info=”{}”][et_pb_row column_structure=”3_4,1_4″ admin_label=”row” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” custom_margin=”0px|||” custom_padding=”0px|||” make_fullwidth=”off” use_custom_width=”off” width_unit=”on” global_colors_info=”{}”][et_pb_column type=”3_4″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_breadcrumbs _builder_version=”3.6″ global_colors_info=”{}”][\/et_pb_breadcrumbs][et_pb_text admin_label=”Text” module_class=”podtytuly” _builder_version=”4.23.1″ global_colors_info=”{}”]<\/p>\n
ZeroFlow is a\u00a0modern variant of controlled gas nitriding ensuring the maximal process effectiveness and efficiency, significantly exceeding the results of traditional solutions. It allows for precise shaping of any nitrided layer composition while maintaining minimal media consumption and post-process gas emissions, meeting the most stringent environmental protection regulations. This is especially important for mass production e.g. gears, pinions, brake discs etc., where the benefits of ZeroFlow technology will be\u00a0most significant.\u200b<\/p>\n
The uniqueness of the ZeroFlow technology lies in\u00a0the fact that during the nitriding process, when the load does not absorb nitrogen from the atmosphere (e.g. during the reduction of nitrogen potential or\u00a0in\u00a0the diffusion phase), the introduction of ammonia into the furnace is completely stopped (zero flow) and the furnace remains tightly closed.<\/p>\n
This is a\u00a0unique feature of ZeroFlow technology and the horizontal type VR and pit type PVR furnaces as\u00a0well as\u00a0automated process lines. It enables the implementation of the most efficient nitriding processes, minimizing process duration, energy consumption, process gas consumption, and post-process gas emission.<\/p>\n
Compared to\u00a0traditional processes, ZeroFlow reduces ammonia and nitrogen consumption many times over, as\u00a0well as\u00a0gas emissions to\u00a0the environment (up to\u00a010 times), and at\u00a0the same time contributes to\u00a0energy savings.<\/p>\n
It is a\u00a0technology that protects the natural environment and supports sustainable development.<\/p>\n
[\/et_pb_text][et_pb_tabs admin_label=”Tabs” module_class=”red-tabs eco-tab6″ _builder_version=”4.27.6″ hover_enabled=”0″ custom_css_main_element=”margin-top: 2rem;||margin-bottom: 2rem;” global_colors_info=”{}” sticky_enabled=”0″][et_pb_tab title=”Overview” _builder_version=”4.23.1″ global_colors_info=”{}”]<\/p>\n
The ZeroFlow technology maintains full versatility of conventional gas nitriding while minimizing media consumption compared to\u00a0competing technologies.<\/p>\n
Horizontal type VR and pit type PVR (including automated process lines) furnaces equipped with ZeroFlow technology belong to\u00a0the family of retort nitriding furnaces with horizontal or\u00a0vertical loading and vacuum purging, available in\u00a0a\u00a0wide range of sizes and workspace capacities. These furnaces are compact, equipped with an internal atmosphere mixer and a\u00a0cooling gas blower to\u00a0accelerate the load cooling in\u00a0the retort. The special design of the retort and heating elements ensure the furnace\u2019s long-term and reliable operation in\u00a0industrial conditions.<\/p>\n
In\u00a0VR and PVR furnaces, the nitriding process is carried out in\u00a0automatic mode with the possibility of combining individual devices into automated technological lines for mass production. The furnace can be\u00a0equipped with nitrocarburizing (FNC) and post-oxidation installations. In\u00a0addition, these furnaces can be\u00a0used for a\u00a0wide range of tempering and annealing processes, which further increases their versatility.<\/p>\n
[\/et_pb_tab][et_pb_tab title=”Advantages” _builder_version=”4.23.1″ global_colors_info=”{}”]<\/p>\n
\/<\/strong>\u00a0<\/span>Accurate shaping of any nitrided layer composition [\/et_pb_tab][et_pb_tab title=”Benefits” _builder_version=”4.23.1″ global_colors_info=”{}”]<\/p>\n \/<\/strong> <\/span>Minimal ammonia consumption, just to\u00a0supply the necessary amount of nitrogen to\u00a0the treated details in\u00a0the tightly closed furnace (as\u00a0opposed to\u00a0the traditional process where the atmosphere is continuously flowing through the open furnace and only a\u00a0small amount is used for nitriding). [\/et_pb_tab][et_pb_tab title=”Industries” _builder_version=”4.27.6″ hover_enabled=”0″ global_colors_info=”{}” sticky_enabled=”0″]<\/p>\n \/<\/strong><\/span>\u00a0Automotive industry<\/strong>: \/<\/strong><\/span>\u00a0Aerospace industry<\/strong>: \/<\/span><\/strong>\u00a0Machine industry<\/strong>: \/<\/strong><\/span>\u00a0Tool industry<\/strong>: \/ <\/strong><\/span>Commercial Heat Treatment<\/strong> \/<\/strong> <\/span>Fasteners [\/et_pb_tab][et_pb_tab title=”Processes” _builder_version=”4.23.1″ global_colors_info=”{}”]<\/p>\n \/ <\/span><\/strong>Nitriding [\/et_pb_tab][et_pb_tab title=”Technology” _builder_version=”4.23.1″ global_colors_info=”{}”]<\/p>\n \/<\/span><\/strong> Nitriding takes place in a tightly closed retort with forced atmosphere circulation. [\/et_pb_tab][et_pb_tab title=” ” _builder_version=”4.23.1″ global_colors_info=”{}”]<\/p>\n \/ <\/span><\/strong><\/span>Process control ensures nitrogen is directed to\u00a0the heat-treated parts for minimal ammonia consumption [\/et_pb_tab][\/et_pb_tabs][\/et_pb_column][et_pb_column type=”1_4″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_gallery gallery_ids=”154046,154053,154060,154067,154074,154081,154088,154095,154102,154109,154116,154123,154130,154137″ posts_number=”1″ show_title_and_caption=”off” show_pagination=”off” zoom_icon_color=”#e2001a” module_class=”seco-products-gallery-new” _builder_version=”4.23.1″ custom_css_overlay_icon=”content:’VIEW GALLERY’ !important;” locked=”off” global_colors_info=”{}”][\/et_pb_gallery][et_pb_text admin_label=”premium library” module_class=”premium-library-button” _builder_version=”4.23.1″ _module_preset=”default” global_module=”156957″ saved_tabs=”all” global_colors_info=”{}”]<\/p>\n PREMIUM LIBRARY<\/span><\/a><\/p>\n [\/et_pb_text][et_pb_text admin_label=”R&D en” module_class=”product_widget_wrap_rd” _builder_version=”4.23.1″ _module_preset=”default” text_orientation=”center” global_module=”167835″ saved_tabs=”all” locked=”off” global_colors_info=”{}”]<\/p>\n R&D<\/span><\/a><\/p>\n [\/et_pb_text][et_pb_text admin_label=”AUTOMATYKA en” module_class=”product_widget_wrap_automation” _builder_version=”4.23.1″ _module_preset=”default” global_module=”167846″ saved_tabs=”all” locked=”off” global_colors_info=”{}”]<\/p>\n AUTOMATION<\/span><\/a><\/p>\n [\/et_pb_text][et_pb_text admin_label=”SERVICE EN” module_class=”product_widget_wrap_service” _builder_version=”4.23.1″ _module_preset=”default” global_module=”167859″ saved_tabs=”all” locked=”off” global_colors_info=”{}”]<\/p>\n SERVICE<\/span><\/a><\/p>\n [\/et_pb_text][et_pb_text admin_label=”SUPLEMENTALS EN” module_class=”product_widget_wrap_supleme” _builder_version=”4.23.1″ _module_preset=”default” global_module=”167809″ saved_tabs=”all” locked=”off” global_colors_info=”{}”]<\/p>\n SUPPLEMENTALS:<\/span><\/p>\n [\/et_pb_text][et_pb_text admin_label=”Product brochure” module_class=”suplementals_product_brochure suplementals_wrap” _builder_version=”4.23.1″ _module_preset=”default” locked=”off” global_colors_info=”{}”]<\/p>\n Product brochure<\/a><\/p>\n [\/et_pb_text][et_pb_text admin_label=”Product catalogue vac en” module_class=”suplementals_product_catalogue suplementals_wrap” _builder_version=”4.23.1″ _module_preset=”default” global_module=”169566″ saved_tabs=”all” locked=”off” global_colors_info=”{}”]<\/p>\n Product catalogue<\/a><\/p>\n [\/et_pb_text][et_pb_text admin_label=”Product infographic” module_class=”suplementals_product_infographic suplementals_wrap” _builder_version=”4.23.1″ _module_preset=”default” locked=”off” global_colors_info=”{}”]<\/p>\n Product infographic<\/a><\/p>\n [\/et_pb_text][et_pb_text admin_label=”Product movie” module_class=”suplementals_product_movie suplementals_wrap” _builder_version=”4.23.1″ _module_preset=”default” locked=”off” global_colors_info=”{}”]<\/p>\n Product video<\/a><\/p>\n [\/et_pb_text][et_pb_text admin_label=”dnabook-en” module_class=”suplementals_product_dna suplementals_wrap” _builder_version=”4.23.1″ _module_preset=”default” global_module=”167873″ saved_tabs=”all” locked=”off” global_colors_info=”{}”]<\/p>\n DNA\/BOOK<\/a><\/p>\n [\/et_pb_text][et_pb_text admin_label=”ECO\/BOOK-en” module_class=”suplementals_product_eco suplementals_wrap” _builder_version=”4.23.1″ _module_preset=”default” global_module=”165507″ locked=”off” global_colors_info=”{}”]<\/p>\n ECO\/BOOK<\/a><\/p>\n [\/et_pb_text][et_pb_text admin_label=”product-widget-rfq-en” module_class=”product_widget_wrap_rfq-en” _builder_version=”4.23.1″ _module_preset=”default” global_module=”186100″ saved_tabs=”all” locked=”off” global_colors_info=”{}”]<\/p>\n REQUEST FOR QUOTE<\/span><\/a><\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”4.23.1″ _module_preset=”default” custom_padding=”0px||||false|false” global_colors_info=”{}”][et_pb_row module_class=”secoservice-faq-wiersz” _builder_version=”4.19.2″ _module_preset=”default” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.19.2″ _module_preset=”default” global_colors_info=”{}”][dipl_faq_page_schema closed_toggle_icon=”L||divi||400″ closed_icon_color=”#000000″ closed_use_icon_font_size=”on” closed_icon_font_size=”24px” open_toggle_icon=”L||divi||400″ open_icon_color=”RGBA(255,255,255,0)” open_use_icon_font_size=”on” open_icon_font_size=”24px” closed_toggle_bg_color=”rgba(244,244,244,0)” open_toggle_bg_color=”rgba(255,255,255,0)” admin_label=”DP FAQPage Schema” module_class=”secoservice-faq faq-center-background” _builder_version=”4.23.1″ _module_preset=”default” faq_heading_font=”TitilliumWeb Black|900|||||||” faq_question_closed_font=”TitilliumWeb Black||||||||” faq_question_closed_font_size=”26px” faq_answer_text_font=”Titillium Web||||||||” faq_answer_text_font_size=”24px” animation_style=”slide” animation_direction=”bottom” faq_question_closed_font_size_tablet=”26px” faq_question_closed_font_size_phone=”20px” faq_question_closed_font_size_last_edited=”on|phone” faq_answer_text_font_size_tablet=”24px” faq_answer_text_font_size_phone=”16px” faq_answer_text_font_size_last_edited=”on|phone” border_width_all=”0px” border_width_right=”0px” border_width_left=”0px” locked=”off” global_colors_info=”{}”][dipl_faq_page_schema_item faq_question=”What is the nitriding process?” _builder_version=”4.19.2″ _module_preset=”default” global_colors_info=”{}”]<\/p>\n It is the introduction of nitrogen to a metal or alloy surface (usually steel) in a thermochemical process.<\/p>\n [\/dipl_faq_page_schema_item][dipl_faq_page_schema_item faq_question=”What are the results of nitriding?” _builder_version=”4.23.1″ _module_preset=”default” global_colors_info=”{}”]<\/p>\n It results in\u00a0the formation of a\u00a0hardened surface layer with increased mechanical strength and resistance to\u00a0abrasion and corrosion.<\/p>\n [\/dipl_faq_page_schema_item][dipl_faq_page_schema_item faq_question=”What is nitriding used for?” _builder_version=”4.23.1″ _module_preset=”default” global_colors_info=”{}”]<\/p>\n It is used in the production of low-friction, wear-hardened contact sufraces in power transmission systems, such as: wheels, gear shafts, rings, bushings, bearings, pushers, etc. and for improving durability in cutting tools and extrusion die surfaces.<\/p>\n [\/dipl_faq_page_schema_item][dipl_faq_page_schema_item faq_question=”How is steel nitriding different from carburizing due to the process sequence?” _builder_version=”4.19.2″ _module_preset=”default” global_colors_info=”{}”]<\/p>\n Usually, nitriding is preceded by thermal improvement (with hardening), while hardening occurs after carburizing.<\/p>\n [\/dipl_faq_page_schema_item][dipl_faq_page_schema_item faq_question=”How is steel nitriding different from carburizing due to the process temperature?” _builder_version=”4.19.2″ _module_preset=”default” global_colors_info=”{}”]<\/p>\n Nitriding is carried out at temperatures of 450-600 o<\/sup>C, while carburizing is carried out at austenitizing temperatures, usually 800-1100 o<\/sup>C.<\/p>\n [\/dipl_faq_page_schema_item][dipl_faq_page_schema_item faq_question=”Where are carburizing and nitriding used?” _builder_version=”4.23.1″ _module_preset=”default” global_colors_info=”{}”]<\/p>\n Carburizing is typically used where thicker hardened layers are required, for heavier loads and more massive parts. Nitriding is used in\u00a0thinner layers, where abrasion resistance is the key.<\/p>\n [\/dipl_faq_page_schema_item][dipl_faq_page_schema_item faq_question=”What is the difference between nitrided and carburized layers?” _builder_version=”4.19.2″ _module_preset=”default” global_colors_info=”{}”]<\/p>\n The hardened nitrided layer can achieve higher hardness and lower friction, and exhibit better heat resistance and anti-corrosion properties.<\/p>\n [\/dipl_faq_page_schema_item][\/dipl_faq_page_schema][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.23.1″ _module_preset=”default” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.23.1″ _module_preset=”default” global_colors_info=”{}”][et_pb_code admin_label=”Code” _builder_version=”4.23.1″ _module_preset=”default” global_module=”123774″ saved_tabs=”all” global_colors_info=”{}”] [et_pb_breadcrumbs _builder_version=”3.6″ global_colors_info=”{}”][\/et_pb_breadcrumbs]Retort furnaces for nitriding, tempering, annealing – ZeroFlow Modern, ammonia and energy-saving and ecological gas nitriding process used in VR\/PVR type furnaces. Nitriding and Ferritic Nitrocarburizing (FNC) furnaces. ZeroFlow is a\u00a0modern variant of controlled gas nitriding ensuring the maximal process effectiveness and efficiency, significantly exceeding the results of traditional solutions. It allows for precise […]<\/p>\n","protected":false},"author":2,"featured_media":86511,"parent":5342,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_et_pb_use_builder":"on","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"class_list":["post-82101","page","type-page","status-publish","has-post-thumbnail"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.secowarwick.com\/en\/wp-json\/wp\/v2\/pages\/82101","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.secowarwick.com\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.secowarwick.com\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.secowarwick.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.secowarwick.com\/en\/wp-json\/wp\/v2\/comments?post=82101"}],"version-history":[{"count":80,"href":"https:\/\/www.secowarwick.com\/en\/wp-json\/wp\/v2\/pages\/82101\/revisions"}],"predecessor-version":[{"id":190977,"href":"https:\/\/www.secowarwick.com\/en\/wp-json\/wp\/v2\/pages\/82101\/revisions\/190977"}],"up":[{"embeddable":true,"href":"https:\/\/www.secowarwick.com\/en\/wp-json\/wp\/v2\/pages\/5342"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.secowarwick.com\/en\/wp-json\/wp\/v2\/media\/86511"}],"wp:attachment":[{"href":"https:\/\/www.secowarwick.com\/en\/wp-json\/wp\/v2\/media?parent=82101"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\/ <\/span><\/strong>Maximum efficiency and process performance
\/<\/strong>\u00a0<\/span>High quality and repeatability of results
\/ <\/span><\/strong>Compliance with the environmental protection regulations requirements
\/ <\/span><\/strong>Furnace\u2019s reliable operation in\u00a0an automatic cycle
\/ <\/span><\/strong>Precise control of the nitriding atmosphere directly in\u00a0the retort
\/ <\/span><\/strong>High accuracy of temperature control, uniformity +\/-3o<\/sup>C
\/ <\/span><\/strong>Computer control system based on\u00a0PLC + IPC Siemens standards
\/ <\/span><\/strong>Full automation and visualization of the heat treatment process
\/ <\/span><\/strong>Simple and intuitive furnace operation and process recipe preparation
\/ <\/span><\/strong>Compliant with AMS-2750, AMS-2759 and CQI-9 standards
\/ <\/span><\/strong>Data archiving and reporting system
\/ <\/span><\/strong>Preventive Maintenance function
\/ <\/span><\/strong>Remote Diagnostics
\/ <\/span><\/strong>Compact design<\/p>\nThe benefits of ZeroFlow nitriding over traditional processes are:<\/h2>\n
\/ <\/span><\/strong>Ability to\u00a0use ammonia alone as\u00a0the most efficient nitrogen carrier (without dilution with other gases, e.g. nitrogen or\u00a0dissociated ammonia).
\/<\/strong> <\/span>The utilization of the furnace vacuum evacuation (instead of traditional purging with process gases), which significantly reduces the consumption of process gases (ammonia and nitrogen).
\/ <\/strong><\/span>Precise and dynamic process control by\u00a0directly measuring and controlling the nitriding atmosphere composition inside the furnace using only ammonia and internal dissociation.
\/<\/strong> <\/span>It ensures very high accuracy of forming the required nitrided layer.
\/<\/strong> <\/span>Internal dissociator IAD \u2013 same precision without energy losses
\/ <\/span><\/strong>Minimal operational costs
\/ <\/span><\/strong>Process simulator: ZeroFlow Feedback Control<\/p>\n
e.g. brake discs, gears and pinion shafts, hydraulic pump components, crankshafts and camshafts, sleeves, valve springs, suspension springs, piston rings and pins.<\/p>\n
e.g., gears and pinion shafts, transmissions, etc.<\/p>\n
e.g. sleeves, pins, shafts, rings, cylinders.<\/p>\n
e.g. cutting tools, forging dies, dies for extruding aluminum profiles, die inserts, screws of plastic injection molding machines, mold parts for aluminum casting, press molds, forming fittings, etc.<\/p>\n
e.g brake discs, gears and pinion shafts, hydraulic pump components, crankshafts and camshafts, sleeves, valve springs, suspension springs, piston rings and pins. sleeves, pins, shafts, rings, cylinders. cutting tools, forging dies, dies for extruding aluminum profiles, die inserts, screws of plastic injection molding machines, mold parts for aluminum casting, press molds, forming fittings, etc.
\/ <\/strong><\/span>Fabricted metal products<\/strong>
e.g gears and pinion shafts, hydraulic pump components, crankshafts and camshafts, sleeves, valve springs, suspension springs, piston rings and pins. sleeves, pins, shafts, rings, cylinders. cutting tools, forging dies, dies for extruding aluminum profiles, die inserts, screws of plastic injection molding machines, mold parts for aluminum casting, press molds, forming fittings, etc.
\/ <\/strong><\/span>Machine-building<\/strong>
e.g brake discs, gears and pinion shafts, hydraulic pump components, crankshafts and camshafts, sleeves, valve springs, suspension springs, piston rings and pins. sleeves, pins, shafts, rings, cylinders. cutting tools, forging dies, dies for extruding aluminum profiles, die inserts, screws of plastic injection molding machines, mold parts for aluminum casting, press molds, forming fittings, etc.
\/ <\/strong><\/span>Mint<\/strong>
e.g. cutting tools, forging dies, die inserts, screws of plastic injection molding machines, mold parts for aluminum casting, press molds, forming fittings, etc.<\/p>\n
e.g. cutting tools, forging dies, die inserts, screws of plastic injection molding machines, mold parts for aluminum casting, press molds, forming fittings, etc.<\/p>\n
\/ <\/span><\/strong>Nitrocarburizing (FNC)
\/<\/span><\/strong> Post-oxidation
\/ <\/span><\/strong>Tempering
\/ <\/span><\/strong>Annealing
\/ <\/span><\/strong>Others<\/p>\nZeroFlow gas nitriding process:
<\/strong><\/h2>\n
\/<\/span><\/strong> The nitriding process is controlled by partial or complete closing of the ammonia inflow to the retort and controlled ammonia dissociation inside the retort.
\/<\/span><\/strong> During Zeroflow nitriding, the temperature and nitrogen potential KN are controlled based on the measurement of the hydrogen content in the retort (and not at the furnace gases outlet). The current value of the nitrogen potential (KN) is compared with the set value (according to the recipe) and automatically regulated by the PLC control system by periodically dosing ammonia with a mass valve according to the PID algorithm.
\/<\/span><\/strong> The atmosphere discharged from the furnace is disposed of in order to meet the requirements of gas emissions to the environment.
\/<\/span><\/strong> The controlled atmosphere emissions are processed through appropriate neutralizing equipment such as VOC Thermal Oxidizer prior to being vented\u00a0 into the environment, in accordance with local emissions regulations.<\/p>\nGreen nitriding using the ZeroFlow method:<\/span>\u00a0<\/span><\/h2>\n
\/ <\/span><\/strong><\/span>Ammonia demand is significantly reduced, up to\u00a010 times less than traditional technology
\/ <\/span><\/strong><\/span>Minimal emission of post-process gases meeting environmental protection requirements
\/ <\/span><\/strong><\/span>Vacuum purging instead of gas purging reduces inert gas utilization
\/ <\/span><\/strong><\/span>Precise building of any nitrided layer build-up, configuration, maximizing process efficiency
\/ <\/span><\/strong><\/span>Nitrocarburizing carried out effectively and efficiently using methanol<\/p>\n